Skeeter: He's real brainy.
Scooter: She's athletic.
Skeeter: We're so different...
Scooter: It's pathetic.
She does stunts and
I assist her.
Skeeter: He's my brother!
Scooter: And they tell me she's my sister!A Sub-Trope of the Odd Couple wherein the odd couple are twins, usually identical brothers or sisters. A prominent exception is actually in the former Trope Namer, The Patty Duke Show. It featured identical cousins, who were described as "One pair of matching bookends, different as night and day" in the Expository Theme Tune. Basically, Sibling Yin-Yang for (usually identical) twins. They'll usually embrace using Identical Twin ID Tags to help the differentiation. Sometimes overlaps with Cain and Abel, in which case you might expect Fearful Symmetry. Also frequently overlaps with Foolish Sibling, Responsible Sibling and Red Oni, Blue Oni. Compare Evil Twin. Extreme opposite is Single-Minded Twins or Creepy Twins.
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Anime and Manga
- Tsubasa and Arisa from Arisa. Arisa is loved by everyone at her school, has good grades and is the Class Representative. Tsubasa is nicknamed "the Demon Princess" and is constantly getting into fights and has lousy grades. As it turns out, Arisa is very much a Broken Ace.
- In Aruosumente, the twins Lante and Dante. Lante is cheerful, outgoing, chatty, frilly and can't fight to safe his life. Dante, on the other hand, barely talks at all, keeps to himself, cares only about Lante and is the best fighter in the kingdom, to the point of being called a beast. Interestingly, it's Lante who may be a schemer and capable liar, while Dante is very straighforward.
- Axis Powers Hetalia: the Boisterous Bruiser America and the Shrinking Violet Canada are only implied to be twins, but they fit in fairly well. The show also has sweet, softhearted Italy Veneziano and his brother, the temperamental, hotheaded Italy Romano.
- Baka and Test: Summon the Beasts: the Nice Guy Hideyoshi and the Jerkass Yuuko. Further differences include that Hideyoshi is not smart enough to qualify past Class F (the bottom of the barrel), while Yuuko is in Class A (the best), and Hideyoshi is a beautiful singer but Yuuko is completely tone-deaf.
- Bleach: The sweet House Wife-in-trainingnote Yuzu and the rough Tomboy Karin.
- Blue Exorcist is essentially about a pair of these, as both Okumura brothers are very different: Yukio is a stoic Badass Bookworm Teen Genius who subverts Half-Human Hybrid due to being sickly when young, while Rin is a Hot-Blooded Book Dumb Almighty Janitor who is the inheritor of Satan's power. They fell into this when younger as well, with Yukio being a Shrinking Violet Cute Bookworm (and still has shades of both still), while Rin was a Pint-Sized Powerhouse loner.
- Digimon Frontier: Kouji and Koichi. Kouji is arrogant and kind of a jerk at first, working by himself because he thinks the others will only drag him down. As time goes on, he shows a much kinder side. His Digimon forms are wolf-based and his element is light. Meanwhile, his twin is similar in appearance but far more soft-spoken and willing to be in the group once he's de-brainwashed. And, his Digimon forms are lion-based and his element is darkness (Dark Is Not Evil.)
- D.N.Angel: Riku and Risa even come out and say that their personalities are completely different. Risa is very girly and rather shallow (most of the time), while Riku is tomboy-ish and more down to earth.
- Durarara!!: Mairu and Kururi Orihara actually invoked this. They actually flipped a coin to decide which girl got which trait. Strangely enough, their roles (Mairu as the Genki Girl and Kururi as The Quiet One) switch when they're on the internet. Even weirder is the fact that they don't consider themselves separate people.
- Eyeshield 21: The Kongo twins Unsui and Agon. Unsui has a shaved head like a monk (it's sort of a theme at their school) is intensely hard working, diligent, cautious, a very good athlete and basically a decent guy. But Agon (with a distinctive dreadlock hairstyle) is the series' Jerk Ass, a Jerk Jock to the extreme (including the womanizing, which apparently started in middle school) who gets away with being a sociopathic thug, slacker and general all-around asshole because he is a talent seen only once in a hundred years. It emphasized by the fact that 'A' and 'Un' represent "beginning and end" aka birth and death.
- Fushigi Yuugi gives us easygoing, kind, polite Amiboshi contrasted to Hot-Blooded Jerkass Suboshi. Heck, even their weapons are different: Amiboshi has a flute which he can use for Mind Control on his opponents (for good or evil purposes), and Suboshi prefers to just smash through everything with a Killer Yo-Yo. Even their clothes reflect just how opposite they are: Amiboshi wears a blue tunic, and Suboshi wears an orange one. (At least in the series; in promo artwork, they are very frequently dressed exactly alike.)
- Takuma and Kazuma from Gakuen Babysitters. The former is perpetually cheerful, and the latter is perpetually teary-eyed.
- Although the later being conceived in a less-than-natural fashion, Amata Sora and Kagura Demuri from Aquarion Evol fit this to a T. Kagura is a hotblooded warrior from the enemy land raised to be a savage killing machine, while Amata is an insecure, shy and gentle guy with issues regarding his mother's apparent abandonment when he was a kid. Them being opposites of each other is actually a plot point.
- Glass Fleet's Vetti and Cleo exemplify this trope. Though, their personalities are passed off as them having been raised separately, with the younger one subjected to mental and sexual abuse, giving him his screwed up personality.
- Hekikai No Aion: The twin sisters Shizuki and Yuzuki. Shizuki is a Manipulative Bitch and an Ill Girl, in the other hand, Yuzuki is a Ditz and a Dumb Muscle
- High School Star Musical has two pairs - Nayuki's younger sisters, Tsumugi and Yuki, are more typical and aren't major characters. But separated twins Tsubasa and Itsuki - who aren't even known to be related - have a large part of their conflict revolve around how they've developed into this since being separated.
- I'm Gonna Be an Angel!: Noelle (the light) and Silky (the darkness) as described by Mikael. Mikael and Raphael might also count.
- The Fubuki brothers in Inazuma Eleven. Shirou is a gentle, calm and timid defender, while Atsuya is a Hot-Blooded and rude forward. Coincidentally, Shirou's hair is bluish-gray and Atsuya' s hair is pink.
- Kiss x Sis: We have Emotional Red Oni Ako and Soft-Spoken Blue Oni Riko.
- Lucky Star: Kagami and Tsukasa. The former is a somber Tsundere while the other is a ditzy Cloudcuckoolander. When asked about this by Konata, they point out that they are fraternal twins.
- Fuka and Fumika Narutaki of Mahou Sensei Negima!. The former's the trouble-making class pankster while the latter's constantly worried about how the former's pranks will get them in trouble as she gets dragged along.
- In Miracle Girls, Tomomi is an outgoing and athletic tomboy while Mikage is feminine, studious, intellectual, and bad at sports.
- Gundam SEED has Kira and Cagalli. The former is quiet, polite, and kind to a fault. The latter is brash, flippant, and has quite a temper. Also one's a boy and one's a girl. And one is genetically engineered to be physically "perfect", while the other...has superior physical abilities without any genetic alteration.
- Monster: Anna and Johan Liebert. Anna's a nice, sweet girl who practices aikido and delivers pizza as a part-time job. Johan is the title character.
- Yuma and Yuna Kashiwagi from Pani Poni Dash!. Yuma is an extreme extrovert, Yuna is an extreme introvert. Yuma goes so far as to actively sabotage Yuna's attempts at being more accepted just to keep eyes on her.
- Pandora Hearts has Alice and the Will of the Abyss. Alice is boisterous, tomboyish, ill-mannered and she likes to wear dark dresses as opposed to her sister, who is lady-like in every way and always wears light-colored dresses. Their opposite personalities, tastes and clothing are what makes obvious which twin was in control of Alice's body in the flashbacks.
- Pokemon Omega Ruby Crimson Passion & Pokemon Alpha Sapphire Indigo Wisdom has twins Alpha and Omega. Omega is a calm boy with blue Tsurime Eyes while his older brother Alpha is a hot-headed goofball with red Tareme Eyes.
- Ranma ˝: Towards the end of the manga, there is Pink and Link, identical twin girls from a village of herbalists that neighbours Shampoo's village of "Chinese Amazons" and who practice different branches of an unnamed "Martial Arts Herbalism", a fighting style that revolves around plants and herbalistic concoctions. Pink, who is usually smiling, is a wicked and vicious girl who loves to poison people. Link, who is usually frowning, is a kind and gentle girl who considers it her duty to heal those her sister hurts. Despite these opposite natures, they care for each other deeply and are capable of uniting with singular purpose when given motive... which means that, in their actual appearance in Nerima, they function more like Single-Minded Twins.
- Suiseiseki and Souseiseki from Rozen Maiden are very much this, both including a Tomboy and Girly Girl relationship, but with several more differing characteristic traits. Where Souseiseki is stoic, Suiseiseki is emotional. Souseiseki is serious and collected, while Suiseiseki is mischievous. Souseiseki believes it is the duty for every doll to participate in the Alice Game regardless of personal attachments, while Suiseiseki strictly opposes the Alice Game due to fear of losing her sisters.
- Spirited Away: The identical twin sisters Yubaba and Zeniba. Yubaba is selfish and materialistic; Zeniba, while vengeful at first, turns out to be kindly and humble.
- It's worth noting, though, that the sisters aren't really polar opposites—Yubaba has an introspective side (musing about the nature of humanity and its greed), treats her workers relatively well, so long as they work hard, and genuinely loves her son Boh to the point of spoiling him. Similarly, Zeniba can be just as nasty as her sister—one of her first lines to Chihiro is a threat to rip the girl's tongue out if she says anything about her presence. Miyazaki seems to be deconstructing this trope with the characters, pointing out that unlike fairy tale villains, most adults are both bad and good, with positive and negative qualities alike (a fact suggested by Chihiro eventually calling both sisters "Granny").
- Private Actress has the twins Shuuto and Yuuto, Shiho's clients in one chapter. Older twin Shuuto is a Mr. Fanservice and a famous model, while younger twin Yuuto is just as good looking but a very awkward Fragile Flower. Shuuto, then, hires Shiho to pose as Yuuto's suitor, in an attempt to help him. Massively subverted: Shiho eventually finds out that Shuuto and Yuuto are the same person and a case of Split Personality.
- Saint Seiya has the twin brothers Saga (thoughtful, wise, just until his Superpowered Evil Side kicks in) and Kanon (selfish, scheming, arrogant until he has a Heel–Face Turn.) For major irony, Saga is the Gemini Saint, with Kanon inheriting his position once Saga dies.
- From the villainous side, the twins gods Hypnos and Thanatos. Sure, they are Creepy Twins on their own, and aside from acting similarly , they also have similar creepy eyes. However, most of the times, they are more of this trope because of their personality, as they are textbook examples of Red Oni, Blue Oni with Thanatos as the red oni and Hypnos as the blue oni. Thanatos have much shorter fuse than Hypnos ever had, does show more emotion that Hypnos ever does, will jump into the fight if challenged, and underestimated humans in general. Hypnos however, hates fighting, and will seek ways to avoid fighting, and calmly analyzes his enemies. This is even more prominent in Saint Seiya: The Lost Canvas, where they still share similar personality with their classical counterpart, where when they are defeated and sealed, Thanatos continue cursed Pope Sage pettily and furiously , when Hypnos accepted his loss calmly and congratulates Hakurei instead.
- Saint Seiya: The Lost Canvas continues this tradition with arrogant, narcissist, megalomaniac, self-centered, scheming, sleek and dainty Aspros, with the gritty and self-sacrificial Defteros. And yes, they are the Gemini Saints of their era, where Defteros had to kill Aspros because he showed his true colors, wanting to kill Defteros so that he could be the Pope. After Aspros'death, Defteros takes the Gemini Cloth with him and becomes the new Gemini Saint
- In Saint Seiya Omega we have Gemini Paradox who has a crazy split-personality and good, loving, kind Gemini Integra. Same thing happens. Paradox is beaten by Ryuuho, and Integra picks up the Gemini Cloth afterwards during the Pallas War.
- Samurai High School: Sakakido Kou and his sister Sakakido Tsukiko are Masculine Girl, Feminine Boy.
- Rumiko Takahashi's one-shot The Samurai has identical twin ninja sisters, one of whom is a total nymphomaniac, while the other Does Not Like Men and Hates Being Touched. Woe be unto the person who confuses the latter for the former.
- There, Beyond the Beyond: gives us twin boys both named Virid Visette Viridian, who are summed up quite nicely by their titles: "The Mad Prince" and "The Sane Prince".
- To Love-Ru features Momo and Nana Deviluke, which also personify this trope very well. Momo is a Yandere Chessmaster sex maniac and can talk with plants. Nana is a B-Type Tsundere Ingenue prude and can talk with animals.
- Trigun: Vash and Knives. One is a genocidal maniac and the other is a pacifist. That's pretty different. Vash is also all about how other people feel and love and peace, and Knives doesn't even do empathy for his twin with whom he has an effing psychic link. Vash acts like a fool whenever he can and Knives is all superiority and icy control except when his temper gets away from him. They do have a bit in common still, when you get past the good and evil divide. For instance, scary if you get them mad. Stubborn as hell. Charisma. Way of speaking, when serious, is even a little similar. Pretty good, when you consider they've been separated over a hundred times as long as they were together. When they were kids in the anime, one was unusually mature and one was goofy. No prizes for which. In the manga, they were much more similar, but Vash was more outgoing and Knives was more sensitive.
- Hamel and Sizer from Violinist of Hameln. Hamel is loud, obnoxious and tends to spaz out while his sister Sizer is calm, sensible and serious. He's arrogant and loves to boast while she's a bit shy and doesn't like a lot of attention. Them being opposites is also emphasized by the fact Hamel is half demon while Sizer is half angel, and she starts as a villain while Hamel is the hero.
- Rua and Ruka (Leo and Luna, respectively, in the dub) from Yu-Gi-Oh! 5D's. Rua is a rowdy, cocky duelist who overestimates himself. Ruka is quiet, introverted and is usually the one to notify Rua when he goes too far.
- The original series' Yugi and Yami Yugi can be counted as this if you consider them twins (of the split personality/alternate guy living in your head kind), with a dash of Sibling Yin-Yang.
- the Tenma twins from the spin-off from the original series, Yu-Gi-Oh R. Gekkou is mature, gentle,reasonable and already independent from Pegasus, meanwhile Yakou is very dependent on Pegasus, that he flips his shit upon Pegasus's disappearance and takes over Kaiba Corporation to resurrect Pegasus, effectively becoming the Big Bad, spends his time on screen showing his insanity,gloating off his victory and telling the protagonists he is unstoppable, or ranting about the fact that Gekkou used to be Always Someone Better to him. In their flashback too, they are this. Gekkou is cheerful and always in the spotlight, meanwhile Yakou is gloomy and forgotten or only seen as the inferior version of Gekkou. Their names reflect this too. Gekkou means "Moon Verse" when Yakou means "Night Verse". Lampshaded by Yakou himself in his match against Yugi.
- Michele and Sara Crispino from Yuri!!! on Ice. Michele is short-tempered and uptight, while Sara is friendly and more down-to-earth.
- Jezebel and Dinah in Blacksad: Dinah is a black bear (= dark brown) with a white patch on her chest, Jezebel a polar bear (= white) with a dark patch on her chest. Otherwise, they share face structure, and body and hair type. Personality-wise, Dinah is softer and Jezebel harder, although both have it in them to do what they need, if it's for righteous revenge.
- Ember and Suntop in ElfQuest. She is a fiesty, red-headed partially wolf-blooded mortal Wolfrider who is destined to become the next Chief of the Wolfriders. He is the complacant, magical, blonde, immortal grandson of the mystic leader of the Sun Village and the apprentice of the equally mystic Mother of Memory. Word of God is that they actualy chose these different destinies while in the womb.
- The Flash: Hyperactive, Fun Personified speedster Bart Allen (aka (Impulse) and his collected, scheming, evil clone Thaddeus Thawne (Inertia). Bart even mentions The Patty Duke Show the first time they meet, suggesting they switch places to befuddle their friends. Thad responds by punching Bart in the nose.
- Gregory Stark and Tony Stark in Ultimate Avengers. Becomes a case of Cain and Abel.
- In X-Men Noir, Thomas and Robert Halloway are, respectively, a know-it-all afflicted with Chronic Hero Syndrome and a crude, violent sadist. It's probably important to note that they were adopted by different families after their father died.
- Young Avengers: Caring geek Wiccan and hyperactive badboy Speed.
- Swordquest: Earthworld has Gemini, who is composed of an evil white shade and a helpful black shadow.
- In Silver Surfer: Dawn Greenwood's Establishing Character Moment is when she and her sister Eve see a shooting star (actually the Surfer), Eve wishes to go everywhere and see everything, and Dawn wishes that the star could keep going so everyone could get a wish. Eve thinks Dawn's wasted her wish since she didn't really ask for anything, and Dawn doesn't understand why anyone would want to leave their home town. As an adult Eve's been all over the world, and Dawn still doesn't see why anyone would leave. (Too bad The Call Knows Where She Lives.)
- The Avengers Scarlet Witch and Quicksilver are polar opposites most of the time—Pietro is stern and stubborn and hot-tempered, his sister is gentle and patient and demure. This is especially true of their earliest appearances, where it was easier to define Wanda's personality as "Pietro's opposite". Over the years, however, Wanda has gained a stubborn temper of her own, making her more similar to her brother.
- In Boy Scouts ˝, the Porter twins. Kirstin is a gentle, sweet homemaker. Nicole is a greedy, ruthless money seeker.
- In Empath: The Luckiest Smurf, Hefty and Handy are the Brains and Brawn twins, but are not identical.
- Moon Soldier features ditzy and emotional Usagi and her twin brother, the calmer and more responsible Akira.
- In The Rabbit And The Puppy Kagami and Tsukasa from Lucky Star. Kagami is a Tsundere and Tsukasa is TheDitz.
- Meg's Family Series has Chris and Jillian's twins, C.J. and Tilly. The former basically inheriting their parents' (Lack of) brains, and the latter being a super-genius.
- We are the Chatroom Gems has Yella and Azura Diamond, this story's versions of a human Yellow and Blue Diamond. Yella is cold, yells at a student (Lapis) for wearing a "Say hi if you're Bi" shirt, and is heavily implied to have undiagnosed IED, while Azura is emotional, has no problem with student's sexualities, and says that her depression is "apparently" obvious.
- Eurotrip: The twins Jenny and Jamie are pretty different. Throughout the movie the phrase "worst twins ever" is repeated.
- Hellboy II: The Golden Army has Prince Nuada and Princess Nuala; while they are Half-Identical Twins in appearance, Word of God says they were intended to be as different as night and day in all other respects.
- She's the Man: Sebastian and Viola. He's artsy and musical, and she's athletic and loves soccer. It's even lampshaded near the end of the movie.
- The Reveal in Shock Treatment is the fact that this is the case of Brad Majors and Farley Flavors, who were seperated as infants when their parents died.
- Star Wars: Luke is a blonde, blue-eyed, calm, mild-mannered, naive, mystical, religious Jedi Knight. Leia is a brunette, brown-eyed, quick-tempered, sharp-tongued, worldly-wise, shrewd, practical politician. Interestingly, they parallel their parents' personalities from the Prequel Trilogy, with Luke taking after their mother Padme, while Leia takes after their father Anakin.
- The Star Wars Expanded Universe shows Luke having trouble teaching Leia to be a Jedi. What worked for him (he got a lot of Jedi qualities) won't work for her. Hot temper is not something a Jedi knight ought to have. Especially since she's pregnant with Han's baby while trying to learn.
- The Parent Trap: In the 1998 remake, the twin girls, Annie James and Hallie Parker (Lindsay Lohan), are completely different. Annie is calm, reserved, and rather uptight while Hallie is relaxed, loud, outgoing, and a Big Eater. (Compare Annie with Cody and Hallie with Zack of The Suite Life.)
- Susan and Sharon in the original, to a lesser extent.
- Markus and William Corvinus, from Underworld: Evolution, were twin brothers who respectively became the first vampire and first werewolf. One is scheming and pompous, the other is near-mindless and savage. Unusual in that we never learn if they'd been genetically identical or not, as William is already locked permanently in his wolf-man form at the time the film is set, but they probably were.
- Rock star wannabe Roxy and Young Republican Jane in New York Minute.
- Charlie and Donald Kaufman in Adaptation. have completely opposite approaches to screenwriting and to life.
- In Double Trouble, David is an honest cop with slobby habits, and his brother Peter is an unrepentant cat burglar with a taste for culture.
- The whole concept of Twins is that Arnold Schwarzenegger and Danny Devito play genetically-engineered twins, with Arnold being the product of attempting to make the perfect man and Devito being all the "genetic garbage" they were weeding out of Arnold.
- In The Pretty One, Laurel and Audrey are identical twins. Audrey is self-assured, confident, and popular. Laurel is reclusive and is convinced that she is the inferior of the two.
- Constantine has the aggressive cop Angela, and her twin sister Isabelle who is The Ophelia.
- Polgara and her twin Beldaran in The Belgariad series. The former is dark-haired, has a grim disposition, and grew up to be an immortal sorceress. The latter was blonde, had a sunny disposition, and married young to become the queen of an island kingdom and bear the royal line which would deliver the child of prophecy, before dying young of pneumonia. As Polgara's biography explains, the two were originally much more similar, but their mother tampered with them in the womb to prepare them for their destinies.
- Occurs in Gordon R. Dickson's Childe Cycle series of novels and short stories, in the characters of Ian and Kensie Graeme. Both are Dorsai (Proud Warrior Race Guys). Ian is the epitome of the Warrior - seemingly aloof and intimidating by his sheer presence. Kensie is his polar opposite - warm, caring, social - everything that Ian is not. In the stories it's implied that together the two make up one individual. Ironically, it's Ian who's irresistible to women - without realizing it.
- Double Trouble: Randi likes red, soccer, and is outgoing; Sandi likes pink and purple, schoolwork, and is rather quiet. They do agree that their two-year-old brother is a pill.
- The Brothers Majere; easy going, heroic Boisterous Bruiser Caramon and intense, morally ambiguous Squishy Wizard Raistlin in Dragonlance.
- Lampshaded in The Legendsong Saga. Glynn and Ember are twins who are both physical and personality opposites. Their only physical similarity is the same colour eyes (yellow); personality contrasts include Emberï¿½s musical talents and Glynn being tone-deaf.
- In Dragon Bones, Erdrick is the shy, sensible twin, Beckram is a ladies' man and troublemaker. They look so alike that Beckram often persuades Erdrick to take his place at boring social occasions.
- Shaun and Shem from Finnegans Wake probably count, but it's hard to figure out which is which, due to the book changing their names constantly. All you need to know is one is boring and dull, and the other is really creative and artistic.
- Specifically, Shaun is dull and conformist but successful in society, while Shem is a slovenly outcast but also an artistic genius.
- Owen and Porter from First Person Plural by Andrew Beierle. Owen is a book-reading drama nerd. Porter is a cheerleader-dating football player. Owen is gay, and Porter is straight. They are also conjoined twins sharing one body with two heads. This is incredibly awkward considering that Porter married a homophobic woman.
- Nicky and Alex in the Full House book series grew up to be different, one tough, one shy, although in one episode of the show their father was concerned that their personalities would turn out the other way around.
- The Eiran twins Eamonn and Grainne from Kushiel's Dart by Jacqueline Carey.
- In the original Story Lottie and Lisa by Erich Kästner (aka "Das doppelte Lottchen"), the titular twins had extremely different personalities, which made their place change all the more hilarious, and later difficult. Lisa was a cheerful, bratty tomboy while Lottie was a sensible, serious, prim and proper girl who behaved almost like a grown-up. Most film versions omit this aspect.
- Eve and Alexandra in Master of the Game are a Cain and Abel crossover version — Alexandra is sweet, honest, and innocent, with no ambitions towards running Kruger-Brent, Ltd. Eve is consumed by ambition and the desire to be the center of everyone's attention, and starting from the age of five she's determined to kill and/or ruin Alexandra, who's in the way. (Incidentally, author Sidney Sheldon co-created the much gentler Trope Namer years before.)
- Abby and her twin sister Anna of The Baby-Sitters Club. Anna is musical, bookish, and introspective; Abby is athletic, noisy, and enjoys babysitting. About the only things they have in common are that they both have scoliosis and poor eyesight.
- Dawn and Eve of Piers Anthony's Xanth are literally as different as day and night, from the fact that Dawn is red haired and green eyed, and is like the morning, while Eve is black haired and eyed and is like the night.
- Belle and Samuel from Rolitania are very different, indeed. Belle is popular, sociable, and has thousands of Instagram followers. Samuel, on the other hand, is the Butt-Monkey of the class, a former NEET, and can hardly speak for himself when confronted.
- Both the books and TV version of Sweet Valley High, with the Wakefield twins Jessica and Elizabeth.
- The Tortall Universe gives us:
- In Song of the Lioness, Alanna the down-to-earth Action Girl who dislikes magic, academic pursuits and social games, and Thom the fame-hungry career mage and scholar who thinks he's Above Good and Evil.
- A deliberate subversion of this trope in the next generation with Alanna's daughter and son Alianne and Alan in Daughter of the Lioness, who are neither this nor Single-Minded Twins. Word of God says this was to point out that there's not always some mystical weirdness about twins.
- In Pierce's Circle of Magic universe, Nia the shy, retiring one (with woodworking magic) and Jory the hyperactive, overeager one (with cooking magic).
- Tatterhood and her unnamed twin sister from the Norwegian fairytale are a perfect example of this: Tatterhood is an ugly, but spirited princess who rides on a goat and singlehandedly beats up hordes of trolls and witches, while her sister is a beautiful, but helpless Damsel in Distress. Despite this, the twins are inseparable and get along famously.
- Amoret and Belphoebe in The Faerie Queene: The former was adopted by Venus, the Goddess of Love and Beauty, and became a Proper Lady. The latter was adopted by Diana, the Goddess of Maidenhood and the Hunt, and became an Action Girl.
- Robert L. Stevenson's The Strange Case of Dr. Jekyll and Mr. Hyde: Dr. Jekyll and Mr. Hyde may be considered a variation of this trope.
- Emmeline and Adeline March from The Thirteenth Tale, who are totally passive and excessively violent respectively.
- The twins in Flowers in the Attic Cory is quiet, polite and gentle. Carrie is loud, adamant and forceful.
- Web Serial Novel Correspondence From The Goddess has Lydia Devin, the main character, a snarky aimless twentysomething who slowly gains divinity-level powers over the course of the story, and Elana Devin, her twin sister, who is perfect as perfect can be but doesn't seem to have any powers at all.
- Billie and Joe from The Call of the Wild are said to be as different as day and night. Billie is a sweet but timid dog, but his brother Joe is spiteful and aggressive, even keeping evil Spitz at bay.
- Jacqueline Wilson 's Double Act has Tomboy Ruby and Girly Girl Garnet. This becomes more apparent when Ruby cuts off her braids to distinguish herself further from her sister.
- Squirrelflight and Leafpool from Warrior Cats, especially when they're apprentices. Squirrelflight is sharp-tongued and energetic, and becomes a warrior, while Leafpool is calm and more reasonable, and becomes a medicine cat. They're even compared directly to fire and water once.
- The Millenium Quadrology has Lisbeth and Camilla Salander. Lisbeth is a brilliant hacker with No Social Skills who stands up for abused women and children, and has a strong moral code. Camilla is highly manipulative, does not care about those she considers "weak", and has very little in terms of morals being the leader of a Russian crime syndicate.
- Cilla and Tina from I Miss You I Miss You. Cilla is down to earth and is interested in directing theater while Tina is mainly interested in boys and can be quite petulant.
- Jackie Collins ' novel Chances has Lucky and her brother Dario. Lucky has dark hair and a vigorous personality, and she's extremely ambitious. Dario is blonde and a slacker, more interested in his Porsche than the family business.
- Tobi and Toklo from Seeker Bears. Tobi is a timid, quiet Ill Boy while Toklo is adventurous and more than a little grumpy.
Live Action TV
- Madison and Vida Rocca from Power Rangers Mystic Force. Madison is calm and thoughtful, V is on a permanent sugar high and goes rushing into things with a mad grin.
- Theo and Luen Martin from Power Rangers Jungle Fury. Theo is calm, focused and studious, while Luen is adventurous and outgoing.
- Sister, Sister, with Tia and Tamera Mowry. Separated at Birth, Tia being the mature, smart and responsible one while Tamera was irresponsible and Book Dumb. Their characters in the Disney film version of T*Witches are basically the same.
- Two of a Kind and So Little Time, both with Mary-Kate and Ashley Olsen. The twins played this up in most of their TV-movies as well. Ashley nearly always played the responsible one with Mary-Kate as the wild one. This finally got reversed in Winning London where Mary-Kate was bookworm and straight-A-student Chloe while Ashley was relaxed Lad-ette Riley.
- A few Disney Channel shows:
Zack: I swear, we're not related.
- The Suite Life of Zack and Cody: Sprouse twins. Dylan as Zack the jock and Cole as nerdy Cody.
- Friends gives us twin sisters Phoebe and Ursula, the first being a (mostly) light-hearted and cheery Cloudcuckoolander, with the second being mean-spirited, thoughtless, and, in Phoebe's words, a "real high-powered, driven career-type" (she's a waitress).
- The '80s sitcom Double Trouble. Identical twins Jean and Liz Sagal (younger sisters of Katey Sagal of Married... with Children) play identical twins Kate and Allison. Allison is serious and bookish; Kate is happy-go-lucky.
- Big Good Jacob and Big Bad The Man in Black, Jacob's fraternal twin from Lost.
- Scoundrels, Cal and Logan West, an incompetent burglar/criminal, and an intelligent defense lawyer, respectively. The characters are so different, you can barely tell they're played by the same actor.
- This is a remake of a New Zealand show, Outrageous Fortune, with Van and Jethro West in the same roles (also played by the same actor).
- The good and evil brothers in The Wanderer. Dispite both being played by Bryan Brown it isn't at 'all' difficult to tell Adam from Zachary, the evil cackle gives it away every time.
- iCarly: Sam and Melanie Puckett. The former is almost permanently grouchy, borderline sociopathic, and sarcastic, while the latter is upbeat, outgoing, and perky. Notably, Carly says she can't believe that they're sisters. They agree.
- Lee and Leah, the Separated at Birth twins from the British teen show The Gemini Factor, a rebellious boy and a teacher's pet girl, with a sprinkling of Twin Telepathy. They also tended to wear black and white, respectively.
- Katie and Emily Fitch from Skins. In the beginning Katie is portrayed as the shallow, popular, boy-obsessed Alpha Bitch, and Emily as the sweet, socially-awkward Shrinking Violet (and closet lesbian) who does everything her bossy sister says, until she comes out of the closet and begins dating her girlfriend Naomi. But when both girls suffer a series of severe personal setbacks they handle it very differently, with Katie gaining a lot more depth and maturity, having to hold the family together virtually on her own, and Emily becoming more and more angry and destructive.
- Cathy and Patty Lane from The Patty Duke Show. "But they're cousins, Identical cousins all the way. One pair of matching bookends, Different as night and day."
- SCTV parodied the show, running promos for "Identical Bellhops", "Identical Cheese Hostesses" and "Identical OPEC Oil Ministers", all shoehorning their titles into the familiar theme song.
- Sutton and Emma on The Lying Game. Sutton is a Book Dumb Rich Bitch Ice Queen Alpha Bitch while Emma is sweet, caring and intelligent. The only things they have in common are a love for tennis and for Ethan.
- The Big Bang Theory has Sheldon and Missy Cooper. Missy is an athletically built, charismatic, Southern Belle whom their mother once described as being "dumb as soup." Sheldon is the page image for Insufferable Genius, a Hollywood Nerd, with No Social Skills to the point he does not understand typical human interaction.
- Patricia and Piper Williamson from House of Anubis. Patricia is the bold, Tomboyish, defiant and rude one; Piper is highly talented in piano, very sweet and polite, and much less inclined to make big moves out of fear of failure than her Determinator sister is. It's pretty obvious when you compare their crushes- Patricia likes Jerk with a Heart of Gold Eddie, while Piper likes the Nice Guy Class Clown Alfie.
- Max and Phoebe of The Thundermans share only one trait: their superpowers.
- Bewitched had identical cousins Samantha and Serena. Sam was (mostly) happy maintaining the Masquerade as a suburban housewife, while Serena was a wild party-girl who regularly abused her magic.
- Jeannie and her sister on I Dream of Jeannie. Jeannie is a blonde who wears pink, and while she can be selfish and impulsive, is generally sweet and wants the best for Major Nelson. Her sister is a brunette who wears green and is a lot more malicious, self-centered, and sexually aggressive (constantly going after Tony, who's not interested), and causes a lot of problems whenever she shows up.
- Turns out that every Spellman family member is born with a Polar Opposite Twin in Sabrina the Teenage Witch. The most glaring example is Zelda and Jessebelta. Zelda is an intellectual who values knowledge and culture. Her twin on the other hand speaks like a Southern Belle and describes herself as a "bad, bad girl".
Religion and Mythology
- Older Than Feudalism: Classical Mythology - Artemis, a moon goddess and twin sister of Apollo, a sun god, though originally the Greeks did not identify them with celestial bodies.
- In The Bible, we have Jacob and Esau. Esau is the older one, and he displays a Carpet of Virility and is a skilled hunter. Jacob is younger, and isn't so hairy and prefers to use his brains over brawn. Which enables him to receive Esau's birthright. They were at odds with one another before they were even born—God explains to their mother that her difficult pregnancy came from them fighting in the womb. Though they manage to make peace... several years later.
- According to Jewish tradition, Jacob's cousins/wives, Rachel and Leah, were also twins and had similarly disparate personalities, the former being a quiet introvert, the latter more gregarious and emotional.
- Nissien and Efnissien from the Mabinogion. Their names literally mean "peace" and "not-peace" which, funnily enough, highlights the main theme of the story. Not much is said of Nissien. His sociopath brother, on the other hand...
- The elves of Warhammer fantasy really seem to be prone to this trope.
- High Elf Heroes Tyrion and Teclis are identical twins with radically opposing personalities and skills. Tyrion is proud, fair, noble, athletic and well-spoken, while Teclis is dark, feeble, scholarly, caustic-tongued and bitter. The one is the greatest warrior and commander of his race but has no talent for sorcery, the other is a poor fighter but the most powerful living wizard in this age of the world.
- Another example can be found in the 5th edition Tears of Isha campaign pack, which focuses on the war between Calaidan and Kaldor, twin scions of the High Elf house Coraith, one of whom defects to Naggaroth and becomes an evil Dark Elf while the other inherits the family estates and continues their proud High Elven traditions.
- The Wood Elves have Naestra and Arahan, polar opposite personalities in identical bodies produced when Naestrahan was split into two women due to an unknown event deep in the woods of Athel Loren. They ride a dragon.
- Ravenloft's Laurie and Gennifer Weathermay-Foxgrove are identical twin monster-hunters and proteges of Rudolph van Richten. Laurie is an exuberant tomboy, fencer and pistoleer who dresses like a man, while Gennifer is a demure, sober-minded wizard with closets full of conservative dresses. Also, Gennifer may be an unwitting lycanthrope.
- A number of the gods in pre-Fourth Edition Forgotten Realms were opposed siblings, though they usually looked noticeably different—Shar and Selune (the moon and the dark), Tymora and Beshaba (good and bad luck), Vhaeraun and Eilistraee (drow thieves, often male, and redeemed drow, often female).
- The Devil May Cry series Hothead Dante and calculating Vergil.
- Final Fantasy IV: Palom and Porom. Palom is the bouncy, mischievous user of black magic, and Porom is the serious-minded user of white magic.
- The Get Backers game Jagan Fuuin The Mikado twins: Daisuke is very compassionate and sweet and easily befriends the main cast, whereas his identical twin Kyosuke is cold, emotionless, rarely speaks, and seems robotic. It's eventually revealed that the twins are the same person, namely Kyosuke, who, due to fear of their immense spiritual power, were split into two entities, the "body" and "soul". Daisuke was the soul, and once they were merged back into Kyosuke, he acted much like his "brother" did.
- MOTHER 3: Lucas is shy and withdrawn, while Claus is rash and reckless.
- Street Fighter: Hyperactive Yun and brooding Yang of the Lee Brothers.
- Pictured above: Tokimeki Memorial 2 has the twin sisters Miho and Maho Shirayuki. Miho is a sweet, daydreaming girl who believes in fairies, loves fortune-telling and plushies, and dreams of becoming a scenario writer of stories for children. Maho is a playful, blunt and mischevious street-wise girl, who enjoys fashion and window-shopping, and dreams of becoming a model.
- Vampire: The Masquerade – Bloodlines: The Voerman sisters, stoic businesswoman Therese and emotional party-girl Jeanette, from You eventually discover Therese is a Malkavian, a member of a clan of vampires known for insanity, and her "sister" Jeanette is actually her Split Personality. With high enough Persuasion skill, you can convince the "sisters" to cooperate instead of one "killing" the other.
- The WarCraft universe. Malfurion and Illidan Stormrage, the night elf twin brothers. The former leads his people to druidism as an alternative to the dangerous magic that brought the Burning Legion to Azeroth. The latter insists on tapping both that magic and the power of the demons themselves, is imprisoned for centuries and eventually becomes an Evil Overlord.
- The Sims 2: University:
- The Davis twins are described as "different as night and day" within the game, yet they actually have identical personalities and aspirations. The only real difference between them is their appearances and what they like to talk about. Similarly, the Pleasant twins in Pleasantview are supposedly very different, but have very similar personalities.
- In Strangetown there's Lola and Chloe, in the Singles household, although whether or not they are actually twins is somewhat debatable. Lola is Married to the Job, while Chloe is a Hard-Drinking Party Girl.
- Fire Emblem:
- Adean and Briggid from Fire Emblem Jugdral. Adean is a sweet White Magician Girl who didn't train as an Action Girl because it simply didn't fit her kind nature, while Briggid was a stubborn Lad-ette that was first kidnapped and then raised among pirates.
- Fire Emblem Elibe introduces another pair in Lugh and Ray. Lugh is a cheerful mage (specializes in elemental magic), while Ray is a cold and calculating shaman (specializes in dark magic).
- Fire Emblem Fates features two sets, though they're actually non-identical in both cases:
- The Bruiser Brothers in Super Punch-Out!!. Rick Bruiser is outgoing and hot-blooded, while Nick Bruiser is quiet and cold.
- The Neptunia series has the extrovert Ram and the shy Rom. These twins are also a huge source of irritation for their big sister, Blanc.
- Greg and Sidney Kasal from Trauma Center. Sidney is serious and straight-laced, while Greg is far more relaxed.
- The Ryō twins from Senran Kagura. Ryōbi is a sadist who hates her flat chest, where as Ryōna is a masochist who loves her large rack.
- Saku and Bo from .hack//G.U. are twins taking turns playing one character, Sakubo. You can tell whose is logged on by the character's eyes (Saku has Tsurime Eyes, Bo has Tareme Eyes), hat (Saku has the "sun" side pointing up, Bo has the "moon" side), and their general attitude towards you.
- The Elder Scrolls V: Skyrim has fraternal twin brothers Vilkas and Farkas, in the Companions guild, who are a combination of this trope and Red Oni, Blue Oni. Vilkas is very intelligent, but abrasive, hot-blooded, and not especially friendly to new arrivals. Farkas is generally regarded as being dumb muscle, but much more laid back, difficult to anger, and sweet-natured.
- The titular Super Mario Bros.. Mario is brave, outgoing and hot-blooded, Luigi is cowardly, timid and shy.
- Dahlia Hawthorne and Iris from Phoenix Wright: Ace Attorney: Trials & Tribulations. Dahlia is a ruthless sociopath who has been using her cute and innocent image to get away with murder, literally, for years and Iris is sweet, gentle, and compassionate, and honestly fell for the lead character while posing as her sister because she needed him for a master plan but didn't want to be bothered with actually seducing him.
- CLANNAD: Kyou and Ryou. Long-haired tsundere and short-haired easily-embarrassed sweetheart.
- Higurashi: When They Cry: Mion and Shion Sonozaki. Mion is assertive and bombastic, the leader of her True Companions; Shion is sly and seductive, preferring to manipulate people subtly rather than openly command them. It's even more odd, when you realize that they're acting like each other, thanks to a Twin Switch they made when they were younger.
- Tsukihime: Kohaku and Hisui. One is carefree, energetic and always smiling, while the other is silent with little expression. It's also odd, when you consider that they switched places from when they were children: Hisui was originally carefree and cheerful, while Kohaku was shy and untalkative. Then they got older and things got worse for them (specially Kohaku), so Hisui buried her emotions to help Kohaku stay stable while Kohaku hid her very darkened True Self behind a facade of happiness.
- Averted in Flower of Thanatos sidestory, where Kohaku and Hisui synchronize to point where they are no longer themselves and their personalities fuses into one. Becoming Single-Minded Twins instead.
- Ember and Daystar in the ElfQuest visual novels. Ember is active, bold and like her name in looks and attitude. Brother Daystar is mystical and calm, and blond with pale skin.
- Little Busters! has Haruka and Kanata, who form an All Work vs. All Play duo. In reality, though, these roles were mainly either in response to or outright enforced by their abusive extended family and in the end when they are able to move on from their past and accept one another as friends their personalities become a lot less extreme. Not entirely, though.
- ef - a fairy tale of the two.: The Shindou sisters. Chihiro is an ingenue, Kei is a Shorttank.
- The Kazato twins from If My Heart Had Wings. Asa is the timid one, and Yoru is the blunt one. Their differences in personality are literally night and day.
- It's Walky!: Fraternal twins Beef and Walky. Justified as Beef was actually switched at birth with Walky's real twin Sal as part of Mrs. Walkerton's Separated at Birth gambit, Sal and Walky later, after the truth was uncovered, and used to set up some Not So Different moments between the two of them.
- Sal and Walky again in Dumbing of Age despite not being raised apart this time around.
- LnM: L is energetic and childish, M is laid back and precocious.
- Molly and her clone/twin Galatea in The Inexplicable Adventures of Bob! were raised separately. Both are brilliant, naive, and devoted to Bob, Jean, and each other. But while Molly is upbeat, friendly, and gentle, Galatea is paranoid and megalomaniacal.
- The Order of the Stick has Elan and Nale, who look the same except for a goatee on Nale, but their personalities are complete opposite. Elan is good, naive and Genre Savvy, while Nale is an evil and scheming. It turns out that Elan got his goodness from his mother and his genre savvyness from his father, while Nale got his evilness from his father and his affinity for schemes from his mother. Their opposite is also indicated by their names.
- Gogo and Didi from Bomango. Gogo is a Boisterous Bruiser with a short fuse, a heterosexual Lad-ette, and a Jerk with a Heart of Gold who acts as The Id in their Freudian Trio (Andy is The Ego). Didi is a polite perky scientist and a Lipstick Lesbian who acts as The Super Ego. They're a weird example though, in that Didi slowly budded off Gogo which would make her some kind of clone/daughter, but they see each other as twins and have a more sisterly relationship.
- The Hong twins in Sharp Zero. Elliot is dorky, unorganized, and believes others see him as the evile twin and a screw up. Marcus is the put together Mom Friend, was a straight A student, and never gets in trouble.
- Welcome To Room 305 has the Hot-Blooded ladette Yoona as the older twin to Yoon Sung, a (normally) stoic young man. As young children Yoona was a tomboy while Yoon Sung was a sensitive crybaby. Both twins have tempers when they want to though.
- In Red vs. Blue, North is a relatively Nice Guy who is more than willing to put himself in harm's way to save others, while South tends toward Chronic Backstabbing Disorder, with tragic results for her brother.
- Doki is much different than her twin sister Toki. Both dress somewhat alike but wear different colors: black or purple for Toki, reflecting her enigmatic, yet domineering but secretly kindhearted personality, and pink and white for Doki, reflecting her kind, gentle, and angelic personality. It isn't just that, according to Amoridere, Doki is more morally grounded than Toki is (as in, she wouldn't stoop to schemes or anything illegal to meet her demands, whereas the latter probably and more often than not would), along with being more levelheaded, and, Toki, well, she is described as being one who does what she wants, whenever she so wants to do it, consequences be damned. It was also noted that, when the two were children, Doki was always the shy one, while Toki was more assertive.
- Brownie is very much different than her sister, Brittani, in that Brittani is described as being prim and proper, while Brownie is described as tomboyish. Apparently, them looking different than one another is supposed to reflect that.
- Kamu and her twin sister Kanran are somewhat similar in some personality traits, however, Kamu can be said to be more levelheaded and is typically polite whenever needed, whereas Kanran is typically gluttonous, rude, and usually acts before thinking, making her rather foolish. Likewise, Miren and Citrine, with the former being described as being "Lean and Mean" and the latter being "bright and bubbly".
- Vex and Vax from Critical Role play Red Oni, Blue Oni to each other. Vex is excitable, flirtatious, and emotional. While Vax can be all these things in the right contexts, he's more prone to being composed, sarcastic, and pragmatic. The twins love each other dearly, though.
- They also become champions of gods that are practically night and day — Vax under the god of death, the Raven Queen, and Vex under the god of the sun, Pelor.
- American Dragon: Jake Long: Oracle twins Kara and Sara. The gothic Kara foresees good events in the future and is always gloomy because everything good about to happen gets spoiled for her while blonde and preppy Sara forsees the bad events and is always so happy because any time the horrible things she sees aren't happening is absolutely fantastic in comparison.
- The Angry Beavers: Dagget and Norbert, twin beavers, the latter of whom is sensible and collected and the former of whom is essentially insane.
- CatDog: Cat and Dog, conjoined twins who are essentially the opposite of each other. Cat is sophisticated, risk-avoidant, and short-tempered. Dog is uncultured, reckless, and chipper.
- Day and Night: The Pixar animated short actually took this literally.
- Dragon Tales: Zak and Wheezie, who are even very different colors despite being conjoined. Zak is green and uptight, while Wheezie is purple and a Genki Girl.
- ElfQuest: Suntop and Ember actually brought the Media Watchdogs down on them when their creators tried to get an Animated Adaptation going. Turns out Saturday Morning Cartoons is not the time to reverse genders roles and have a spunky little girl and a mild, intuitive little boy. Or, for that matter, twins with different skin colors.
- The Fairly OddParents!: Wanda and Blonda.
- Kim Possible: Gemini identifies himself as being opposite his twin sister Dr. Director in every possible way, which is mostly accurate. They don't even look much like siblings, let alone twins.
- Kaeloo: Rabbit sisters Pretty and Eugly. Eugly is a kind, friendly Gonky Femme and Pretty is a beautiful yet selfish and manipulative Alpha Bitch who is hated by the rest of the cast.
- My Little Pony: Friendship Is Magic:
- Pinkie Pie and her fraternal twin sister, Marble Pie. Pinkie Pie is bright pink, exuberant, and outgoing, while Marble Pie is a dull gray, reserved, and very shy.
- According to the IDW Comics, the mild-mannered schoolteacher Cheerilee has an identical twin sister named Cherry Blossom who's a professional wrestler.
- The Venture Bros.: Thanks to Divergent Character Evolution - Dean has slowly become a nervous, cowardly Non-Action Guy while Hank has evolved into a Small Name, Big Ego who leaps into danger at the slightest provocation.
- Also Rusty and JJ.
- Gravity Falls:
- The series has smart, serious Dipper and ditzy, energetic Mabel.
- It's later revealed that Grunkle Stan was also a twin. His brother, the real Stanford Pines, was a genius, while Stanley was definitely not. Their different interests were what eventually separated them, and Mabel ends up worried her relationship with Dipper might crumble like theirs.
- Yin Yang Yo! has smart Neat Freak Yin and her less intelligent violence loving brother, Yang.
- The Loud House has identical twin sisters, Lana and Lola —
- Lana's probably the most masculine and tomboyish of her sisters after Lynn, is much nicer and more outgoing, and loves getting dirty.
- Lola, who's arguably the most feminine of the ten sisters, on the other hand, dresses like a princess, regularly competes in beauty pageants and is far more conceited than her twin is.
- America's Next Top Model: Amanda and Michelle Babin, who were contestants on Cycle 7. Michelle is tomboyish and more outgoing, whereas Amanda is more feminine and introverted. Michelle also came out of the closet during the course of the show, just to add another night and day difference to the mix.
- Nikki and Brie, the Bella Twins of Total Divas and WWE fame. Brie is a Granola Girl, who loves being a hippie and Country Mouse - but also is a Hard-Drinking Party Girl. Nikki is The Fashionista and power lifter, who loves anything expensive - while preferring wine and deserts to excessive drinking. Their workout methods are different, with Brie opting for yoga and cardio while Nikki enjoys power lifting to maintain Amazonian Beauty.
- Tokio Hotel: Bill and Tom Kaulitz are identical twins, but dress and wear their hair differently, just to name one difference, to the point that some people don't believe they're identical. One of the more notable differences is Bill's focus on "true love" while (until recently) Tom was only looking for love of the one-night variety.
- The public perception of the Kray twins has traditionally had Ronnie, the younger twin, as pure Ax-Crazy psychopath, and Reggie as quieter and more Affably Evil, even acting as something of a Morality Chain to his brother. There's not necessarily much evidence of this, but that just makes the fact that people want it to be the case an example of this trope in action.
- Twin musicians Chuck (bass) and John (drums) Panozzo of Styx. Chuck is soft-spoken and more down to earth, while John was a wild man and more outgoing.
- Happens to twins in Real Life, as twins growing up together try to develop different personalities to distinguish themselves from their sibling. However this is usually subverted in identical twins - twins that came from the same zygote, not from two different zygotes in the womb - as they are practically genetically identical copies of each other and will share many similarities in personality and preferences even if they act differently. National Geographic has done an article on it.