When two siblings end up rivals.
Let's face it, life is a competition. And more often then not, your first and most consistent competitor can be found sleeping in the next bed.
Siblings compete. They compete for toys, love, food, resources, time, attention... in short, pretty much everything. Usually this is a healthy thing — usually — as a little healthy competition builds character and helps to define one's place within the world and within the family. (If nothing else, they'll toughen you up to the point where you can handle just about anything the other kids are likely to dish out.) Besides, as anyone who actually has a brother or sister knows, sometimes you just have to tease them. Otherwise, what's the point?
Sometimes, though, sibling rivalries are not healthy, and then things can get ugly. Really, really ugly. Because who can know you better — and perhaps have more reason to hate you — than your own sister or brother? When the battle is between siblings, you can trust them to know (if not always do) the things that are going to hurt you the most.
Naturally, the closer the siblings are in age, the more intense the rivalry is likely to be, and the more likely one of the siblings will feel Always Second Best. Extreme cases may result in Can't Catch Up, especially if an Aloof Big Brother is involved. If the parents take sides one of the rivals is bound to become The Unfavorite. When it spills over into romantic affairs with two siblings pursuing the same Love Interest, it can become a Sibling Triangle.
For a Sibling Rivalry turned into good vs evil, see Cain and Abel. In case the siblings in question were friends with each other prior to their falling out, it probably triggers We Used to Be Friends.
For that splendid variant of sibling rivalry that's exclusively reserved for girls see The Glorious War of Sisterly Rivalry
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The Tendo Sisters are a fairly gentle example of the "constant teasing" variant, with Nabiki as the prime instigator, while Tatewaki and Kodachi Kuno exemplify a much darker (and funnier) version of the trope.
Koon Eduan from Tower of God has so many children and the tension in his family can get that large that he made it simple: at age ten, all Koon's must fight one of their siblings in a one-on-one match. Losers leave the family.
Umineko no Naku Koro ni has this as a major part of the basic premise, with the adults squabbling over Kinzo's inheritance.
Lina and Luna Inverse in Slayers, even though Luna never appears. Lina seems to admire Luna (she once admitted Luna was "really cool" to a little girl who also had big sister issues in the manga) even as she's terrified of her—or perhaps more accurately terrified of making her angry. It seems there may be a wee bit of Can't Catch Up motivating Lina.
Usagi and Shingo Tsukino regularly take potshots at one another. Usagi is bigger than Shingo and is thus able to bully him phsically, but Shingo is smarter than her so he's better at not getting caught when he pulls pranks. It's also made explicit that both of them care deeply for one another and their fighting is just old-fashioned sibling bickering.
In Corsair, Canale and Jean-Hughes take this to extremes, with Jean-Hughes having tried several times to murder his brother since the age of eight. When Aura is captured by Jean-Hughes the rivalry rears its ugly head again. Aura and Leti in comparison are a healthy version of this, and Ayace, though not blood-related, has a similar sibling-like rivalry with Aura.
The sickest version of this trope occurs in Ichi the Killer (no surprise there) when two psychotic brothers have a sick rivalry going that ends in torture and mutilation for whoever makes one feel inferior to the other. For instance, they each had sex with two women, then the older brother asked one of the girls who was better. When she said that the younger brother was just a little bit better, he furiously pulled all of her hair out. Then he turned the question to the other girl. Terrified, she said that he was the better one. And then the younger brother cut her nipples off. Later on, they had a fierce contest to see who was better at torturing a captive.
Even more disturbing, the brothers used to be triplets. Their extreme rivalry is the reason they're twins.
Misty from Pokémon set out on her training journey in order to prove her worth to her three older sisters.
Sangatsu no Lion uses this for dramatic backstory. Due to their shogi-dedicated upbringing, Rei, the foster child, and the two Kouda children were rivals in shogi to see who was the best in the family that deserved to continue on toward being a professional. However, what they (or at least, the latter two) were really competing for was affection from their father, since the best received the most attention from him. Rei was unlucky enough to be the best out of the three without much effort.
Sekainohate De Aimashou: Prince Emilio has several brothers. Each rules a fiefdom in his own right and all of them are either jockeying for the imperial throne or trying to protect themselves from the others who are jockeying for the throne. It's essentially sibling rivalry raised to the level of a cold war.
Snow White and Rose Red in Fables. They're mostly past it now, but flashes of their backstories reveal that Rose was once so jealous of Snow she behaved in ways that could fairly be characterized as evil.
The male Robins, particularly Dick Grayson (the first Robin) and Jason Todd (Robin II), although it's almost entirely on Jason's side. Jason also has a rivalry with Tim Drake (Robin III), who he sees as his replacement. Damian Wayne (Robin V) had a notable rivalry with Tim Drake, who he saw as his rival in not only being Robin, but in being Bruce Wayne's son (the two can't be in the same room without Damian whipping out the "you're adopted" insult), and essentially usurped Drake as Robin. Notably averted with Damian Wayne and Dick Grayson, with Damian actually preferring to work under Dick instead of Bruce.
In the Uplifted series, it is Hanala and Rael Jarva. While initially amicable, Hanala and Rael quickly come to resent each other once Hanala returns to the fleet completely changed by her experiences on Earth. Instead of the sweet girl he remembers, he is faced with a competitive, antagonistic and violent sister with a fundamental difference of opinion regarding the future of their people.
Lucky Star After Story has the Yoshida sisters, Tomoyo and Hiroko. Tomoyo is the older sibling at age 22 when she was introduced. Hiroko is the younger sibling at age 18 when she was introduced.
Empath: The Luckiest Smurf has Hefty and Handy as dueling twin brothers. Note that it is a friendly rivalry, as they both simply want to be recognized as being more important than the other. Tapper likens their relationship to be "like Esau and Jacob", with Hefty being Esau and Handy being Jacob.
Mean Girls 2. Mandi and Tyler, though oddly the dislike comes entirely from his side and Mandi, despite being a bitch to everyone else seems to have some sisterly feeling for him, even declaring him off limits to Chastity and calling his father (her stepfather) "our Dad". He's also the only character she's never directly mean to.
Twin gunfighters Kid Shelleen (good) and Strawn (evil) in Cat Ballou. Subverted in that no one knew Strawn was Shalleen's brother (due to his facial disfigurement) until after Shalleen shot him. Both were played by Lee Marvin.
Thor and Loki in Thor, but it's much more bitter from Loki's point of view than Thor's until Loki's Face-Heel Turn. Odin seemed to inadverently encourage this since he said that either one of them could be king.
Implied in X2: X-Men United, since Bobby Drake's brother Ronnie calls the cops claiming that Iceman and the others are holding his family hostage soon after finding out he is a mutant.
Miles and Mark Vorkosigan from the Vorkosigan Saga. Given their respective capabilities it's a good thing they prefer to "score" by pulling each other's chips out of the fire.
Sibling Rivalry defines the Weasley family dynamic in Harry Potter, with each successive boy's efforts to outshine the others at something reaching its peak when Percy becomes an unctious, grasping prig. Fred and George may look like they've opted out of the competition but their goofball antics actually earn them a great deal of attention while Ginny's privileged position as the youngest and the only girl puts her on a level where none of the boys can compete. And poor Ron feels overshadowed by all of them. Being the best mate of The Boy Who Lived doesn't always help, either, especially during those moments when it seems like Harry's become yet another (foster) brother with whom he cannot compete. Ron's ultimately successful attempt to overcome this personal demon represents a major turning point in the seventh book.
The first sequel has this with Susan and Lucy. Susan is angered that Aslan seems to favor Lucy, while Lucy is bitterly upset when Peter takes Susan's side because she's older and (usually) wiser. It doesn't help that Susan is very stressed due to how they're in a Narnia very different from the one they knew, so she's unable to see things that Lucy actually can due to her unshakeable faith. When she finally manages to do so, Susan apologizes to Lucy and confesses that she did want to believe her, but her inner fears held her back.
Roger Zelazny's The Chronicles of Amber is centered on the convoluted rivalry and shifting alliances among seven siblings jockeying for their father's throne. (Not all of them want it, but they all have preferences as to who should get it, and perhaps more importantly strong opinions about whom they don't want to have it.) Corwin and Eric in particular take it to Cain and Abel levels, though in later books it becomes less clear which one is which.
Robin Hood in all of its many versions: the underlying plot driver is the sibling rivalry between King Richard and Prince John and in some versions Will Scarlet is Robin's illegitimate half brother.
Septimus Heap: Septimus and Simon, about the ExtraOrdinary Apprenticeship.
In A Song of Ice and Fire, House Frey take this to extremes. Lord Frey is on his eighth wife and has children by all of the previous seven, as well as several illegitimate children and plenty of grand- and great-grandchildren. There is so little love lost between them all that news of a family death elicits more calculation of the effect on the line of succession than grief.
Occurs in the Branion fantasy series among the royal family of the titular country.
In book 1, the heir's mother believes him to be soft and unworthy — his younger sister, however, is ruthless, tough, and viewed as a better potential ruler. Cue sibling rivalry.
In book 3, the royals are all bastards, following opposing religions. The first and third leadLa Résistance against their father, while the second does his best to thwart them.
In Galaxy of Fear, for the most part Tash and Zak get along very well. They're a year apart and both are traumatized by losing their family and have to cooperate in their struggles to survive with a Resentful Guardian who takes them from one dangerous place to another. As they adjust more fully, their guardian comes to like them more, and they acquire skills that help them with the danger, they don't need each other as much and develop more individually. While they never stop looking out for or loving each other, and they tend to have different enough interests that much competition is averted, elements of this creep into the later books of the series. Particularly The Hunger, in which Zak starts feeling like The Unfavorite.
Much of the plot of The Chathrand Voyages is ultimately revealed to have been set in motion by sibling rivalry by way of Evil Sorcerers. Arunis and Macadra are brother and sister, approx. three thousand years old, on-and-off conspirators and perpetual rivals who are each determined to become the most powerful magic-user in history, whatever it takes. Arunis intends to unleash the Swarm of Night to destroy the world, so that the Night Gods will be impressed enough to make him one of them; Macadra is less omnicidal, having subverted the empire of Bali Adro to use as her tool to Take Over the World. Both their plans hinge on the Nilstone- which from the end of the first book on, the protagonists happen to have, leaving them caught between the two.
There is an eleven-way rivalry between the Malagash princes in The Chronicles of Magravandias, but particularly bad are Gastern, Almorante, and Bayard. They are the strongest three, the others tend to latch onto whichever brother they like best or fear most. Their sister Varencienne refuses to have anything to do with it.
War of the Spider Queen has this in the backstory, between Pharaun's siblings Greyanna and Sabal. Pharaun got involved in the rivalry, supporting Sabal. Greyanna killed Sabal, but Pharaun killed Greyanna.
In Blood's Pride, this is a serious problem for the family of the governor of the Shadar. He had four children. One was abandoned as a child because of a physical "deformity". The other three have decidedly rocky relationships. Eofar, the only son, doesn't actually like the power-and-glory focus of his culture very much, and clashes with his sister Frea, who likes those things just fine and considers Eofar to be weak. The youngest daughter, Isa, (initially) wants to a proper Norlander, which gives her a measure of conflict with both (since Eofar tries to dissuade her and Frea is the person her culture says she has to beat to prove herself worthy). The situation is not helped by the secrets they keep from each other - Eofar knows that Frea's dreams of a glorious homecoming are impossible but doesn't say so; Frea inadvertently caused the death of their mother in order to prevent the rescue of the abandoned daughter, then blamed the death on Isa; and Isa was accidentally the cause of the abandonment (and also knows Frea's secret but has been pretending not to). And then the abandoned daughter, Lahlil, turns out to be a) not dead; and b) rather dangerous.
The Bible especially Genesis has this as a recurring theme to the point that it named two tropes Cain and Abel and Jacob and Esau. A major turning point in Genesis is Joseph's story where he subverts this trope and forgives and reunites with his brothers.
The Crane brothers in Frasier fairly run on this trope. Even when they're not actively feuding or competing, they bicker constantly and aspire to out-snark, out-class, and out-psychoanalyze each other on a daily basis, often without even realizing what they're doing. When they wound up in couples therapy with a renowned marriage counselor, he told them that they would never stop fighting as long as they lived, unless they never spoke to each other again. Of course they reject this as a solution because they acknowledge that ultimately they love each other too much.
On a more episodic scale, Daphne becomes extremely jealous of Frasier's new girlfriend, Claire, because she and Martin take a huge shine to each other and begin acting like father and daughter (and Martin starts enthusiastically shipping Claire with Frasier). Daphne has always been as close to an adopted daughter to Martin as it is possible to be, and responds to this new competition by furiously vying with Claire for Martin's attention.
Martin (about Claire): Don't you love her laugh? It's like music.
Daphne (anxiously): You-you used to think my accent sounded musical. Didn't you?....Marty?
Martin: Oh yeah, but now I'm used to it.
While Jackson and Miley compete a fair amount, since Jackson is the Butt Monkey Miley usually ends up on top on Hannah Montana.
Stefan and Damon Salvatore from The Vampire Diaries. Stefan and Damon were best friends before Katherine Pierce came between them, changing the relationship between the Salvatore brothers forever. The rivalry only got more intense when both brothers end up competing over Elena Gilbert, Katherine's doppelganger.
Mary and Buddy from Cake Boss, although they're not so much "rivals" as "she's determined to drive her brother insane on camera For the Evulz" by losing cakes, seemingly erasing a recording that Buddy was going to use as a special effect, coercing a client into painting the baking room a hideous Pepto-Bismol pink, selling a pre-sold batch of crumb cake and then demanding an amazing birthday cake. Naturally, Momma has to make sure they don't kill each other. Additionally, Buddy has three other sisters but they don't drive him anywhere near as crazy as Mary does.
While not actual siblings (though they are Platonic Life Partners) CJ and Toby from The West Wing are a lot like this trope, constantly sniping at and being passive-aggressive to each other while vying for Jed or Leo's attention and approval the way siblings do for their parents.
The two eldest Borgia siblings, Cesare and Juan, despise one another. The cunning, intelligent Cesare bitterly resents the fact that his father practically forced him to become a Cardinal while his Too Dumb to Live, Spoiled Brat little brother becomes heir to the family estate and gets the military position he himself always wanted. And Juan, fully aware that everyone thinks he's an Inadequate Inheritor, becomes wildly insecure about his position of power (and over-compensates for it by being an arrogant idiot).
The Hardy Boys Nancy Drew Mysteries: Of the good-natured, teasing variety between Frank & Joe Hardy, though all bets tended to be off when both brothers were interested in the same female...and Frank wasn't above shoving all the heavy physical work off on Joe, either. And don't get Joe started when Nancy Drew and Frank were anywhere in the same room together...
Suggested but ultimately averted in a episode of Bones, when Booth's son Parker met his newborn baby sister Christine. At one point, Parker was seen taking a pair of scissors to some family photos, indicating that he was jealous of his new baby sister. At the end of the episode, it was revealed that he adored Christine and was cutting the photos to create a mobile to hang over her crib.
On the singing competition Nashville Star, Angela Hacker and her young brother, Zac Hacker, were respectively the winner and runner-up of Season 5.
Bud and Mikey Roberts of JAG, although only on rare occasions.
Subverted in Malcolm in the Middle. While Malcolm and Reese jockey constantly for dominance over trivial things (due largely to their close ages), persistent jealousy, competition, or resentment over big issues, either from Reese over Malcolm's intelligence, or from Malcolm over Reese's happiness, is conspicuously absent from their relationship.
Jaye and Sharon in Wonderfalls. Despite reconciling in the very first episode, they snip and fight over the course of the series. Possibly at its best when Jaye takes an entirely unprovoked shot at Sharon in an article that her family doesn't even know Jaye wrote:
"...a place where a mother's love, a father's compassion, a brother's protection, and a sister, thirty-five...
Smallville: Oooooooh boy. The Earth-2 trio of Lex, Tess, and Clark have this pretty severely. All three of them are technically evil due to being raised by E-2Lionel, it does frequently devolve into Cain and Abel, but most of the tension between the three is focused in their desires to just not be the one Lionel stops caring about. Lex lost before the Earth-2 universe was on the show, but a twisted version of this was still clearly present to a degree between Clark and Tess.
The Lion in Winter has this trope in spades as Prince Richard, Prince Geoffrey and Prince John all angle to become the heir to their father's throne.
In Twice Charmed, Anastasia and Drizella compete over who will win the Prince.
Team Fortress 2—The reason why RED and BLU are fighting is because of a historic feud between brothers Redmond and Blutarch Mann.
Note that this rivalry started as soon as the two were born and had a chance to look at each other, and not even death stopped it, as they just got back up as ghosts and tried to get their mercs to send each other to hell first.
Magina the Anti-Mage and Terrorblade the Soul Keeper in Dota
And in Dota 2, Lina the Slayer and Rylai the Crystal Maiden even though they weren't related to each other in the first Dota.
Tekken has the beautiful Nina and Anna Williams. That's 20+ years in the making.
Main character Hawke and younger brother Carver in Dragon Age II are naturally predisposed to this. Carver has a lot of inferiority issues that don't really get better as the game progresses, though he and Hawke still love and care for each other as siblings. It doesn't help that the only way Carver will survive is if Hawke is a mage; chances are good that Carver will join the Templars, the very people who police/oppress mages.
If Bethany survives instead, party banter will also make references to this being Carver's relationship to her. Apparently he didn't take it well when his twin turned out to be the only magical child while he was normal, which was aggravated further by being an inferior warrior to their elder brother/sister. It's also possible to set up a sibling rivalry between Hawke and Bethany, but the player really has to work for it.
This is the essence of the entire plot of Baldur's Gate, starting with Charname fighting against his half-brother Sarevok in the first installement and culminating in a war between Charname and the other 5 strongest children of Bhaal.
Kayle and Morganna have this in the Order vs. Chaos variety. Both come from a race of creatures that are essentially angels who upheld order throughout the universe, with Morganna being the Fallen Angel who saw their form of order as tyranny against individuality, and Kayle being the stoic general who must now bring her sister to justice.
Nasus and Renekton are brothers who were once protectors of a place called the Great Library. Renekton protected it from evil, but over time he became more and more unstable as he fought more evildoers. Eventually it undid his sanity, and he turned on his brother. Before the two could settle their score, they were pulled through to Runeterra by the league's summoners. While Nasus offers his knowledge to the summoners, Renekton wants nothing more than to see his brother dead.
There are other siblings who aren't hostile to each other in the lore, but that doesn't stop them from being pitted against one another in League matches. This can include Garen vs. Lux, Katarina vs. Cassiopea, and Darius vs. Draven.
In Defense Of The Ancients, at first the Slayer Lina Inverse and Crystal Maiden Rylai Crestfall have no business each other, but in Dota 2, they were retconned into sisters (losing their surnames) and their rivalry was said to be 'the stuff of legends' beyond their opposingelements. Rylai is a little more naive and friendly, but Lina is said to have more advantage for being smarter and guile. They're both by default on the Radiants, but this won't stop them from being pitted for a Cat Fight.
In Heroes of Might and Magic II, the rivalry between Roland and Archibald Ironfist for their late father's throne drags all of Enroth into war (the older Archibald being the more evil of the two). Despite this, the brothers still care about each enough to keep their rivalry from reaching Cain and Abel levels. Neither brother is willing to actually kill the other in their ending. Canonically, Roland wins, and he has Archibald Taken for Granite (which in this setting isn't too bad). In a later Might and Magic game, the brothers ultimately settle their differences when Archibald helps save Roland from the Kreegans and Roland convinces his wife Catherine (who is less inclined to be merciful to Archibald) to exile Archibald instead of executing him.
Usually Mario and Luigi are on good terms but there relationship occasionally has shades of this. It is rather jarring to see Mario angrily grind his brother's foot and growl at him, all while attempting to look like a good sportsman, if Luigi wins against him in Mario Golf: Toadstool Tour.
Charlotte and Angela Olsen from The Overture are consistently fighting and bickering among each other for there mother's affection. It gets so out of hand that the two physically fight while there mother begins labor.
Their mother, Helen, very much had this with her older sister, Rita, over perceived Parental Favoritism. The youngest sister, Amy, likes to think of herself as the detached outsider but turns out to be Not so Above It All. Witnessing all this between their mother and aunts prompts Daria and Quinn to start improving their relationship to avoid a Generation Xerox.
Ruffnut and Tuffnut in How to Train Your Dragoncan work together as a team with a lot of effort... but they still spend more time beating the hell out of each other than they do fighting anything else.
Fry had a rivalry with his brother Yancy in the backstory of Futurama, with a recurring theme of Yancy stealing Fry's ideas and stuff. To the point where it seemed like he'd stolen Fry's name after his disappearance! It turns out Yancy named his son in memory of the disappeared Fry, who went on to accomplish everything he dreamed of.
Drew and Stu Pickles from Rugrats have been arguing and fighting since they were babies, as seen in a Flashback episode.
Rocket Power had two cases of this. Most notably Twister and his older brother Lars when their respective crews compete against each other in a hockey match or some other contest. Also, one episode took Otto and Reggie's rivalry on the snowboard slopes Up to Eleven with a major Downer Ending.
Stewie and Bertram from Family Guy, even though they're really half-brothers. There was even an episode with the same name as this trope involving them.
In ThunderCats (2011) Tygra is Lion-O's adoptive brother. They have a pretty good rivalry going on, with Tygra always seeming to come out on top in "everything except the crown". Still, they're close enough that Tygra helps bail Lion-O out of a fight with an angry mob, saying he's always got his brother's back.
Eli and Peyton Manning. Of course, pretty much every football fan in America would JIZZ IN HIS PANTS were they to face one another in the Super Bowl - the closest approach was the 2007 season (Peyton's Colts were upset by the Chargers in the Divisional Round; Eli's Giants won the Super Bowl over the hitherto undefeated Patriots). In their regular season matchups, Peyton has proven himself to be the better Manning, defeating Eli all three times as of 2013. They have played the trope for humor in a TV commercial that showed them playing juvenile pranks on each other while visiting the NFL Hall of Fame with their parents.
The Harbaugh brothers, both NFL coaches, are another American football example. They have coached against each other twice, on Thanksgiving Day in 2011 and in the Super Bowl in February 2013 (nicknamed the "Harbaugh Bowl" for obvious reasons). John's Baltimore Ravens defeated Jim's San Francisco 49ers both times.
Seriously averted by Venus & Serena Williams who subjected the world to several lackluster tennis finals since they couldn't seem to go all-out against each other.
Liam and Noel Gallagher, formerly of Oasis. There's a bootleg single titled "Wibbling Rivalry" which is just 15 minutes of the brothers hurling abuse at each other during an interview.
Cruelty is common in the animal kingdom, but sharks still stand out as radical (no surprise, really) when it comes to their reproduction process. They are live-bearing and usually have up to fifteen embryos, but only one or two of them actually emerge. Where do the rest of them go? Take a guess.
Ed and David Milliband, respectively Energy and Climate Change Secretary and Foreign Secretary under Gordon Brown, were the two front runners for the Labour Party leadership (and thus the Leadership of the Opposition) after the 2010 elections that put David Cameron's Tory-Lib Dem coalition in power. Ed ran as a more lefty Brownite, David as a centrist Blairite; Ed won.
Although we say they were the front-runners, we should say that David was the odds-on favourite, and Ed was seen as something of a dark-horse candidate.
Ray and Dave Davies of The Kinks. Their onstage brawls were so bad that it led to a five-year ban from American venues.
Basketball players Pau and Marc Gasol have a rivalry of necessity; they play for different teams (the Chicago Bulls and the Memphis Grizzlies, respectively). That said, when they go up against each other they don't hold back. Pau, the older brother, is probably "winning", being on a much more successful team (he had spent most of his pre-Bulls career with the Los Angeles Lakers) and dwarfing Marc in nearly every positive stat category.
On the other hand, they play together on the Spanish national team, and they lead it. "Gasol to Gasol...and it's in" is pretty common whenever Spain is playing.
Candace Bergen has stated that as a young child she felt an intense "sibling rivalry" with an inanimate object: her ventriloquist father Edgar's famous dummy Charley McCarthy.
Seventies/Eighties singing family The Nolan Sisters appear to have split into two separate rival factions who are mutually not at home to each other. Let us call these the Provisional and Official wings of the Nolan family, as it does appear to have got this bloody and this Irish. Relations were soured when the oldest sister made abuse allegations against her (now deceased) father that were hotly denied by the horrified rest of her family. It was pointed out that the oldest sister is bankrupt and in desperate need of the money only a shock/horror autobiography could bring in. Offered a lucrative reunion tour and recording deal, the rest of the sisterhood retaliated by cutting the oldest out of the contact. On top of this, a sixth sister who left the band just as they became famous was miffed to discover the sisters were reforming, and she had not been invited. Lawyers have been brandished and opening shots fired. Offical family history has been airbrushed to make it look as if there were only ever four Nolan Sisters (Maureen, Linda, Bernadette and Colleen). Anne and Denise Nolan are said to be just a wee fecken' bit offended that they no longer exist and are seeking to prove their corporeal integrity, to the satisfaction of Church, State and Courts. (If nothing else, they are credited on the first few LP's and an awful lot of TV work the girls did....) Watch this space.
In a poisonous business rivalry, German brothers Rudolf "Rudi" and Adolf "Adi" Dassler, formerly partners in the family's shoe business, split in 1947. Each founded a new sporting goods company—Rudi founded Ruda, which soon became Puma, and Adi founded Adidas. Both companies were (and still are) based in the small town of Herzogenaurach, which soon picked up the nickname "the town of bent necks" because townspeople constantly looked down at strangers' feet to see what shoes they wore. The town's two football clubs were split, with one sponsored by Adidas and the other by Puma. Workmen who were called to Rudi's home began wearing Adidas shoes; when Rudi saw their footwear, he invariably told the workers to go into the basement and pick out a free pair of Pumas. The corporate rivalry cooled down after both brothers died in the 1970s; now neither company is controlled by either branch of the Dassler family. (And it eventually led to a Dark Horse Victory as Nike surpassed both.)
Animals and birds that have litters, especially predators. A kill will be fought over by the siblings, and weaker ones do not always survive. Some bird species will even push weaker siblings from the nest. Or fake siblings, in the case of cuckoos and cowbirds.
Perhaps the ultimate sibling rivalry is among live-bearing sharks. Stronger young consume the weaker INSIDE THE WOMB. By birthing time, only one is left.