A set of twins who look and act for all the world like they're identical, except for the miiinor
detail that one's male and the other's female.
It's common, especially in drawn or animated media where the creator has complete control over the appearance of the characters, to use brother-sister twins as each other's Distaff Counterpart
and Spear Counterpart
. They often display identical twin tropes, such as Twin Telepathy
, especially if they are Creepy Twins
. It's a way to make sure that twins, even if they're not identical, are immediately identifiable as such
if it's relevant to their characters, and there are no other visual cues to show that siblings are fraternal twins instead of just regular brothers and sisters.
This is, of course, vanishingly rare in Real Life
- any set of twins that isn't identical won't be any more likely to resemble each other than siblings born years apart, and if the twins have different sexes then that means they're not identical (or one has an extremely rare genetic disorder). Of course, some siblings do have a Strong Family Resemblance
. Also, this could happen if one identical twin is Transsexual
and the other isn't.
Compare to the rare real-life phenomenon of semi-identical twins
, where the twins have identical genes from their mother and different genes from their father, and thus can be the same sex or opposite sexes. This could lead to an Uncanny Family Resemblance
if the sperms are similar enough.
This trope is perhaps the most glaring example of Always Identical Twins
Compare Opposite-Sex Clone
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Anime & Manga
- From the Marvel Universe:
- Andrea & Andreas von Strucker (a.k.a. Fenris), and Jeanne-Marie (Aurora) & Jean-Paul (Northstar) Beaubier. Both have superpowers that are activated by touching each other, though the latter pair also have powers on their own.
- Brian and Betsy Braddock used to be Half-Identical Twins (Betsy's Caucasian body was naturally blonde and resembled her brother a bit). They aren't any more, they aren't even the same ethnicity anymore, hard to imagine anyone would think they are related at this point, let alone twins.
- In the original continuity of Legion of Super-Heroes, Lightning Lass easily posed as her dead brother for one story, but was revealed because she didn't have an Adam's Apple. Much later, it was shown that her planet is almost all twins, but the twins were generally depicted as identical.
- An interesting case was a story arc in the Buffy the Vampire Slayer comic (the "Season Zero" between "The Origin" and "Welcome to the Hellmouth", published in 2003) where she goes to Las Vegas. The villains are a pair of conjoined twins: a male vampire and a female mortal. They didn't particularly look alike, but the fact remains that conjoined twins are identical by definition and always the same sex, so a pair that are opposite sexes is a case of Artistic License - Biology.
- Somewhat squicky example from the 2000 A.D. strip Nikolai Dante: Alexandr and Alexandra Romanov are twins, lovers and specially enhanced killing machines that can create and throw nano-mines. Oh, and they can fuse themselves into one deadly grotesque, six limbed form.
- In Marvel Star Wars, Vila and Denin aren't exactly the same. You can see from the second link that Denin is taller and a little broader across the shoulders. Still, after Denin died Vila was able to impersonate him.
- Sidney and Toots the twins in the Bash Street Kids (a comic strip in The Beano).
- Zipi y Zape: The twins look exactly the same... except for their hair color.
- The Official Fanfiction University of Redwall has an excuse for this; in one of the original printings of the book Redwall, the character Killconey swapped between male and female pronouns thanks to a typographical error. (According to later printings he's meant to be male, in case you're wondering.) In the OFUR, this has resulted in there now being two of him, one male and one female. The female one is generally referred to as Konnie to avoid confusion. She's technically more of an Opposite-Sex Clone, but they think of each other as twins.
- Ash and Caiden from VOCALOID Forever, along with Rin and Len Kagamine listed below.
- Grodyn and Rhejya from The Servants Of Ungoliant.
- The Animaniacs fan series Zany To The Max has Zak Warner and his sister, Ko. Taken Up to Eleven by conjoining them.
Films — Animation
Films — Live-Action
- In Jack and Jill, Adam Sandler plays the title twins. This is even unintentionally lampshaded when one of Jack's co-workers asks if they are "identical or fraternal".
- Viola and Sebastian in She's The Man (which is loosely based on Shakespeare's Twelfth Night — see below) look so alike that Viola can pass for a young version of Sebastian.
- In A Series of Unfortunate Events the Quagmire triplets are "absolutely identical," so how the Baudelaires tell whether they're talking to male Duncan or female Isadora is a mystery — although Isadora is illustrated with subtly longer hair. But at least the two brothers Duncan and Quigley never share a scene. Jacques and Kit are an aversion, as the book does not mention any similarity. At all. If anything, there's more similarity between Jacques and Olaf.
- In Wolves of the Calla, the fifth book of Stephen King's The Dark Tower series, almost all births in the village where the story is set are Half-Identical Twins; this is an explicitly unnatural (and evil) effect, however.
- Ser Jaime and Queen Cersei Lannister of A Song of Ice and Fire. The fact that their parents were cousins might have helped. They're also Twincestuous.
- As a result, once Jaime starts to grow a beard in the third book, it becomes a very important symbol of their growing distance.
- In Kathryn Lasky's Starbuck Twins Mystery series of books for children, fraternal twins Liberty and July Starbuck are described as indistinguishable from one another save for the fact that Liberty's hair is long, and her brother July's is short. They also display Twin Telepathy.
- As children, Thom and Alanna, of Tamora Pierce's Song of the Lioness series, were so much alike in face and body shape as to be mistaken for each other, if dressed alike. The only distinguishing feature of the twins at that time was the length of their hair. Both were short and skinny, with copper hair and purple eyes. When Alanna visited Thom at age eighteen she commented on his beard and height, suggesting he grew up to be taller than her. (It makes sense that this stops applying as it would be highly unlikely that male and female twins would be so similar looking as children and adults.) When Alanna cut her hair and dressed in Thom's clothes to leave for the palace, she notes that she looks just like Thom. Coram (the servant that traveled with her and was the only one able to tell them apart), didn't notice the switch until they stopped for lunch.
- Continuing from the example of Star Wars above, Leia and Han's first two children, Jaina and Jacen Solo. Timothy Zahn, who wrote the novels in which they first appear, deliberately modeled them after the Luke/Leia duo. In this case though, it makes a little bit more sense, since they are raised together.
- In Donna Tartt's The Secret History the twins start out similar, but in the end turn out to be two completely different people because one of them has a breakdown and the other turns into a Shrinking Violet.
- Heinlein's Time Enough for Love involves a couple of female genetic scientists creating a pair of Half-Identical Twins for Lazarus Long: two redheaded women named Lazuli and Lorelei, or Laz-Lor. Lazarus calls them his "identicals" even though they're not exactly, being girls. And then they engage in a threesome that is either Twincest, Brother-Sister Incest, or father-daughters incest, depending on how you interpret the relationship. Please keep in mind that Lazarus himself is a pretty blatant Author Avatar.
- Lazarus also recounts a story about a young pair of slaves he once bought to free. They were sold to him as genetically engineered opposite sex identical twins. When he finds out the girl is pregnant, he delves deeply into the possibility of this for fear of her child being inbred. After extensive analysis, he decides that it is scientifically impossible for them to have been created as claimed and the slaver was just trying to bump up their price.
- Lazarus also bought a pair of slaves he bough to free that had been produced by careful genetic engineering that ensured that while they were brother and sister had no genetic relationship (having been created from perfectly complimentary gametes, each bearing different halves of each parent's genes). They were sold as a novelty, with complete documentation included in the package. Since they know they're full siblings, they had to be taught why it wouldn't be a good idea for their children to produce children with each other.
- Um — these two are the same incident. The second is more accurate; Lazarus determines that the twins could have been engineered as claimed, and he proceeds on that assumption.
- P.C. Hodgell's Chronicles of the Kencyrath has heroine Jame and her Half Identical Twin brother Torisen. Jame is frequently mistaken for her brother, and once she's better known, he is mistaken for her — but only once, because that's when he stops finding it amusing and decides to grow a beard.
- The legendary immortals known only as the Twins in Trudi Canavan's Age Of The Five trilogy appear to be this to begin with - they were originally not only identical, but conjoined. They separated themselves with magic to avoid detection, and some time afterwards, one of the twins changed from female to male using similar magic. It was really confusing how one could be female and the other male given their history, and the reference to 'the change' is really easy to miss...
- In Sheri S. Tepper's Sideshow, two of the main characters are conjoined twins of different genders. This is justified in that they were both born intersexed, with ambiguous genitalia. The doctors asked their parents for their opinion on what to do, and while the father was certain that the first one was male (the Virgin Mary had told him so), the mother thought it would be nice to have a little girl. Naturally, the two run into some problems at puberty, since they share a circulatory system, but they each identify as the gender they were assigned and raised as.
- Edgar & Ellen
- Poppy Z. Brite's novel The Lazarus Heart features identical twins, one of whom is a transgendered woman.
- In Maggody and the Moonbeams, Dahlia insists that her twins are "identical", because they look a lot alike to her and she's convinced it'll get them successful Hollywood careers. The contrary fact they're different sexes is ignored, as she doesn't actually know what "identical" means in this context.
- In Orlando Furioso, Ricardetto takes advantage of being always mistaken for Brademante to woo a princess who fell in love with his twin sister. He claims to have been turned into a man by a grateful water nymph.
- Jobeth and Tommy in Clive Barker's The Great and Secret Show.
- Averted in Lev AC Rosen’s All Men of Genius: Based on William Shakespeare’s Twelfth Night, Violet does disguise herself as her twin brother Ashton, but only to people that don’t know them. People have no problem telling Violet/“Ashton” and Ashton/“Ashton’s cousin Ashton” apart.
- Power Rangers RPM has the peppy twin geniuses Gem and Gemma. They have several superficial differences if you look close enough, but you have to look very close- not because the differences are minor, becuase they aren't, but because the twins in question are just that single minded.
- Justified in a Law & Order: SVU episode, where what appear to be Half-Identical Twins turn out to have been born as identical twin males. One twin's genitals were badly injured by a botched circumscision, and a crackpot doctor convinced the parents he'd grow up happier if given a sex change to female (s/he wasn't).
- Tragically Truth in Television there was apparently a real rash of this kind of thing back in the 70s, when cutting edge thinkers had decided that gender was just a matter of socialization. Turns out it's a little more complicated than that. See The Other Wiki: David Reimer. It happened more than once because the first doctor, John Money, who performed it wrote medical articles stating that the procedure went well without aftereffects, because he didn't like the results he got — they conflicted with his theory.
- The short lived FOX series Mental had the part about a botched circumcision resulting in a sex change. It was all fine, until the "girl" ended up lighting him/herself on fire for no apparent reason and kept seeing him/herself in the mirror without a face. The protagonist (a rebellious psychiatrist) realized what was going on. The "girl"'s true identity as a male was trying to push its way to the surface. "She" didn't even have proper female genitalia, just a prosthetic designed to look like one. The crackpot who convinced her father to do this planned to give "her" a vagina when "she" was 18. (Because every girl waits until she's 18 before having sex or having a Date With Rosie Palms, and wouldn't notice the difference because No Periods, Period is normal.) Naturally, when "her" boyfriend finds out the truth, he runs away in disgust. At the end, "she" gets a boyish haircut and decides to try to explore the male lifestyle, even though, without certain body parts, the experience would be far from complete.
- Butch Lesbian "Walter" from German series Hinter Gittern Der Frauenknast ("Behind Bars - the Women's Prison") has a twin brother who's apparently indistinguishable from her without his beard. Which they used in one episode to change roles, allowing her to escape and him to get closer to several female prisoners.
- The Big Bang Theory averts this by giving Sheldon a twin sister, Missy, whose face does not resemble his. Sheldon explains the scientific errors behind this trope in his typical Sesquipedalian Loquaciousness. Howard replies to this, "Hallelujah!" (Missy is rather attractive.)
- Pictured above, Vocaloid's Rin and Len Kagamine are often portrayed this way; for example, in "The Daughter of Evil" series. Officially, they look suspiciously similar (same eye color, same hair color, same height) and are opposite genders, but they're technically "mirror images," not twins. Various fanon incarnations make them twins, lovers, both, or something else entirely.
- Older Than Steam: Sebastian and Viola from William Shakespeare's Twelfth Night, are so much alike that people mistake Sebastian for Viola (who for reasons of plot has disguised herself as a man).
- Siegmund and Sieglinde from Die Walküre.
- Coricopat and Tantomile from Cats. Mungojerrie and Rumpleteazer also count if they're siblings and not mates.
- Vent and Aile in Mega Man ZX seem to be like this... That, or they're just two versions of the same person. It depends on where you look.
- Similarly, Raul and Fiona Gureden, who were male and female versions of the same character in Super Robot Wars Reversal, were made into twins for Original Generations.
- On a similiar note, Viletta Badim and Ingram Plisken have the same deal in Super Hero Operations, and were later made into clones.
- Palom and Porom from Final Fantasy IV may qualify for this: While the artwork, particularly the sprites, lack sufficient detail to be certain whether they were meant to be identical or simply share a number of similar traits and style of dress, there is a distinct theme of similarity coupled with reversal; not only the sexes, but elements of personality (Palom is boastful and rude, Porom reserved and polite [when not berating her brother]), their style of dress (both are pictured wearing red and green outfits, but one's is red where the other's is green, and vice versa), their use of magic (Palom uses the destructive Black Magic, Porom uses the healing/supportive White Magic), and hairstyle (the sprites show a right/left reversal between the two, otherwise being identical; the portraits show Porom's hair looking well-groomed and Palom's hair looking rather messy). However, by Final Fantasy IV: The After Years, puberty and years of different lifestyles have taken their toll, making them look very noticeably different from one another. Also Porom dyed her hair pink for no particular reason. That might make them seem a bit dissimilar.
- In The Last Blade 2, a woman impersonates her dead twin brother, Kojiroh, a member of the Shinsengumi, in order to bring his killer to justice. She ends up living the rest of her life under the charade, taking on her brother's identity as a tribute to him.
- Alfred and Alexia in Resident Evil: Code: Veronica. In fact, the resemblance is so good that Alfred is able to convincingly pretend to be Alexia for several years after she was frozen in order to make people think she was still alive. Kind of explained in that they are really clones.
- Nox and Matin Catorce are identical brother and sister twins from Blind Justice ~Torn souls, Hurt Faiths~ by Zektbach in the beatmania series. Both twins also have special swords that are identical, although one represents Hope and the other Despair.
- Tate and Liza, twin Gym Leaders in Pokémon Ruby and Sapphire. They look so similar that it's a common mistake to think Tate is also a girl, thus making them fully identical.
- James and Francine Garrett, twin co-owners of the Atomic Wrangler in Fallout: New Vegas. Fran is... not attractive because of it.
- Ayra's children Larcei and Ulster, from Fire Emblem: Seisen no Keifu.
- Eagle Eye Mysteries: The title protagonists, Jake and Jennifer Eagle. Besides the obvious gender differences, he's a red-head and she's brown-haired.
- It's not normally obvious due to their normally different outfitsnote and hairstyles, but Rahal and his sister Rania Suikoden V are near-identical. When Rahal is required to disguise himself as a woman, the player is likely to not realize what happened at first, and instead wonder "How did Rania get here, and what happened to her glasses?"
- Subverted in BioShock Infinite. Robert and Rosalind Lutece seem to be this at first, though this is the least abnormal trait they display. They actually turn out to be different versions of the same person from parallel universes.
- Averted and lampshaded in Ever17. You is confused as to why Sara and the Kid don't have the same abilities or look similar despite being twins, at which point it's explained with some amusement that biology doesn't work like that.
- In the Murder Mystery Visual Novel Jisei, one of the main characters has an identical twin sister who you don't see until the end of the game. It turns out that she and her brother were private investigators, and she deliberately sent her brother in as a mole to check out the murder scene. She was the telepathic voice helping the protagonist to solve the crime all along.
- Averted to some extent with the demons Zepar and Furfur from Umineko no Naku Koro ni, who are twins despite having differently coloured hair and different overall colour schemes—and then there's the fact that we don't know who's the boy and who's the girl. However, they do have the same eye colour and wear the exact same outfit.
- Roger and Lily Pepitone in College Roomies from Hell!!!!!! (from which the trope takes its name).
- Walky and Sal from It's Walky!
- Elliot and Ellen from El Goonish Shive have decided to use this as a cover story for Ellen, who's Elliot's Opposite-Sex Clone.
- Samael and Mara from Picatrix are twins. In an added twist, Mara inherited none of the magical ability typical of their demonic race while Samael inherited double.
- Janus and Arthur from The Adventures of Wiglaf and Mordred, as illustrated here
- Kau and Shala from Drowtales, seen briefly here.
- Thoss and Thlassa of Juathuur.
- John and Jade from Homestuck. Even before The Reveal, they are very similar in appearance and behavior (much more so than Rose and Dave).
- Though this could be partly due to the fact that their biological parents looked pretty similar as well.
- Litter mates Bear and Bryony from Catena don't act alike, but except for their hair and Bear's chin they're pretty nearly identical. Their other sister Patches, on describing Bryony, even comments to Bear that "She looks like you, only, you know, pretty."
- Sam and April of Dragon City look identical aside from gender and April's glasses, but according to the Fourth Wall Mail Slot they actually are identical, gender in dragons is influenced by incubation temperature (as in crocodiles) rather than genes. Every other set of twins in the comic are obviously fraternal, even having differently colored scales.
- Averted in Princess Chroma with April and Sonny, who look no more alike than any other brother and sister.
- Red vs. Blue subverts this with North and South's faces—while both have very light blond/white hair, they look quite a bit different—but it's played fairly straight with their armor, which is subtly different colors of purple and green. When only one is on screen, it's hard to tell which it is unless they're standing next to someone (South is shorter than North) or you've gotten really good at picking out the different colors of purple (South is lighter and North is darker).
- Phil and Lil on Rugrats. (Although it could be argued that most babies look alike anyway. However, in the spinoff, where the kids are 10-13, Phil and Lil can still pass for each other with a simple change of clothes and a wig). One episode has the twins managing to distract a robber just by removing Lil's bow to make her look exactly like Phil.
- Robbie and Rosie in the 1980s UK stop-motion kids' series Cockleshell Bay.
- The Wonder Twins from Superfriends, Zan and Jayna.
- In Justice League Unlimited, the Ultimen are based on the Super Friends team members who were created for the show instead of the comics. Their versions of the Wonder Twins, Downpour and Shifter, are so similar it's very difficult to tell them apart. Shifter doesn't have much in the way of the Most Common Superpower, so even examination of the chest area only works if they're standing side by side to compare. They even share a voice actor.
- Justified since they are not actually twins, but somewhere between clones and genetically engineered super beings.
- She-Ra and He-Man. Both have super-special-sword powers, and blond hair, and extensive muscling in super-form. Though to be fair, it's hard to mistake Adam for Adora, or the other way 'round.
- Scooter and Skeeter from Muppet Babies.
- Ben 10 episode "Camp Fear" features brother-sister twins who fit this trope to a T.
- Lem and Ada from the 1980's Strawberry Shortcake series. Supposedly only their dog, Sugar Woofer, could tell them apart, despite Ada wearing a bow and Lem wearing a hat at all times.
- Before the Retcon in King of the Hill, Peggy and her brother Hoyt were stated to look very much alike, however because of the retcon they look nothing like each other.
- The Interesting Twins from Beneath the Mountain in Codename: Kids Next Door.
- Dipper and Mabel from Gravity Falls are a somewhat subtler example: their basic design is pretty much the same, but they dress and act quite differently, have hair different lengths, etc. Also Mabel has braces while Dipper has a (rarely seen) birthmark on his forehead.
- Desna and Eska, Avatar Korra's fraternal twin cousins, are described by The Legend of Korra writers as "androgynous, creepy twins".
- While extremely rare (only three to five known cases), there are cases in which otherwise identical twins can be of the opposite sex. More info here.
- One real-life occurrence that can produce boy-girl twins who are genetically identical (but who do not bear a strong visual resemblance), is when a zygote that is 46,XY (a normal healthy boy), undergoes incomplete mitosis in the womb. One of the resulting zygotes is 46,XY (still a healthy boy), and the other has a missing Y chromosome, and so is 45,X (a girl with Turner Syndrome). Genetically identical apart from the sex chromosomes, although Turner syndrome produces some fairly noticeable differences (physical and otherwise).
- When two sperm fertilize one egg, which is rare, the resulting embryo almost never survives. However, there is a unique (in recorded history) case of "semi-identical twins": a pair that inherited exactly the same set of genes from their mother, but share only half from their father.
- There's also the less rare instance where fraternal twins of opposite sexes simply have such a strong family resemblance that they can pass for each other... at least til puberty, anyway.
- Can happen when one identical twin is transgender and transitions later in life, or if a genetically male individual grows up female due to one of many medical situations where that could happen, whereas the other twin grows up male without the condition. As of 2011 there are now news stories about a pair of teenage identical twins where one is trans.
- A variant: Adam and Stephen are identical twins but one is straight and the other gay.
- And let's be honest with ourselves: Most pairs of fraternal twins start out this way. They're babies. They look like babies.