History Main / DoubleInLawMarriage

* In ''Manga/MahouSenseiNegima''[='=]s finale, it's shown that the twins Fuka and Fumika ended up marrying twin princes from the magic world.

* The ''Franchise/{{Touhou}}'' fandom has the [[ShipMates double ship]] of [[OurVampiresAreDifferent Remilia]]/[[MindOverManners Satori]] and [[CreepyChild Flandre]]/[[DissonantSerenity Koishi]]. Note that until the 2019 manga ''Webcomic/TouhouChireikidenFoulDetectiveSatori'', [[ShipsThatPassInTheNight the Scarlets and the Komeijis had never actually interacted in canon]].

* Natsuki Enomoto and Yuu Setoguchi are the first pair to become an OfficialCouple in the ''Musicc/ConfessionExecutiveCommitteeLoveSeries''. Meanwhile, Natsuki's little brother Kotaro is in love with Yuu's younger sister, Hina. [[spoiler:Although Hina has a crush on Koyuki at first, she eventually reciprocates Kotaro's love after Koyuki graduates]].

* Natsuki Enomoto and Yuu Setoguchu are the first OfficialCouple to get a RelationshipUpgrade in the ''Musicc/ConfessionExecutiveCommitteeLoveSeries''. Meanwhile, Natsuki's little brother Kotaro is in love with Yuu's younger sister, Hina. [[spoiler:Although Hina has a crush on Koyuki at first, she eventually reciprocates Kotaro's love after Koyuki graduates]].

* Although it's only part of the act that they keep up to appear human, the Cullen/Hale "kids" ''appear'' as this to outsiders in the novel ''Literature/Twilight''. Alice Cullen is with Jasper Hale while her "brother" Emmett Cullen is with Jasper's "sister" Rosalie Hale. It's implied that the family puts on some variety of this trope whenever they all move to a new location together and that Bella and Edward will be folded into the deception now that they're together and both vampires.

* In Creator/OrsonScottCard's ''Literature/HomecomingSaga''--a loose retelling of Literature/TheBookOfMormon [[RecycledINSPACE IN SPACE!!!]]--brothers Nafai and Issib marry sisters Luet and Hushidh.

* The ''Franchise/{{Touhou}}'' fandom has the [[ShipMates double ship]] of [[OurVampiresAreDifferent Remilia]]/[[MindOverManners Satori]] and [[CreepyChild Flandre]]/[[DissonantSerenity Koishi]]. Note that until the 2019 manga ''Webcomic/TouhouChireikidenHansokuTanteiSatori'', [[ShipsThatPassInTheNight the Scarlets and the Komeijis had never actually interacted in canon]].

Alice and Bob are siblings. So are Charlie and Dana. Alice marries Charlie, while Bob falls in love with Dana. The gender configurations can vary--it could be two sisters who each marry one of a pair of brothers, or any variation including QueerRomance. In other words, it's any time one pair of siblings marry another pair of siblings. Someone marries the sibling of their own sibling's spouse.

* In ''Princess Belle-Etoile'', a king and his brother marry two sisters. Unfortunately, there is a third sister and the king and his brother don't have a third brother for her. She marries an admiral instead and becomes jealous. (Their children, three of the king's and one of the brother's, are then abandoned together, and despite being raised as brothers and sister, [[KissingCousins the king's daughter and the brother's son manage to fall in love and end up married]].)

** Other Arab fairy tales reflect the tradition of KissingCousins; a woman falls in love with a man and that's a problem because she's betrothed to her first cousin. If he's willing to give her up, this is often amiably resolved by the new bridegroom offering the cousin a bride who is his cousin.

* In ''[[Literature/XWingSeries The Bacta War]]'', we learn that Lanal Darklighter is Gavin's aunt on both sides of the family, because she is both his mother's sister and his paternal uncle's wife.

* Although it's only part of the act that they keep up to appear human, the Cullen/Hale "kids" ''appear'' as this to outsiders in the novel ''Literature/Twilight''. Alice Cullen is with Jasper Hale while her "brother" Emmett Cullen is with Jasper's "sister" Rosalie Hale. It's implied that the family puts on some variety of this trope whenever they all move to a new location together, and that Bella and Edward will be folded into the deception now that they're together and both vampires.

* ''Literature/ABrothersPrice'' has this trope seen as very positive, since it means closer bonds between families and makes cousins more like sisters. When Cullen is married to the older Whistler sisters, he hopes to get their cousins married to ''his'' sisters.

** Also doable in the second generation of ''Genealogy of the Holy War'' with, well, any two brother-sister pairs, but notably [[FanPreferredCouple Arthur with Phee and Ced with Tine]]. This can also potentially be two pairs of KissingCousins if Patty is with with Lester and Febail with Lana. Even more in the case of the last two couples together; their mothers Edain and Briggid were identical twin sisters, so this involves [[BrotherSisterIncest marrying two pairs of genetic half-siblings to each other]].

*** In the DLC route of ''VideoGame/FireEmblemFates'', it's possible to do up to a ''quadruple'' version of this trope by getting the Nohr and Hoshido royal families to marry each other. There are four possible combinations: the first would have Elder Princes and Elder Princesses (Ryoma/Camilla and Xander/Hinoka) plus Younger Princes and Younger Princesses (Takumi/Elise and Leo/Sakura), the second has Elder Princes and Younger Princesses (Xander/Sakura and Ryoma/Elise) plus Elder Princesses and Younger Princes (Takumi/Camilla and Leo/Hinoka), and the other two have one Elder Prince with an Elder Princess and the other with a Younger Princess while the Younger Princes reverse which is paired with Elder and which with Younger (Xander/Hinoka, Ryoma/Elise, Leo/Sakura, and Takumi/Camilla or Xander/Sakura, Ryoma/Camilla, Leo/Hinoka, and Takumi/Elise). Plus there are even more variations where only two or three of the siblings marry each other. For a ''Birthright'' only example, one could marry Hinoka and Sakura to ninja brothers Kaze and Saizo (then marry their children Asugi and Midori to each other). And of course, there's the possibility to pull this off with the second generation. If Azura marries a man who produces a daughter, and the female Avatar does the same, then Azura's son Shigure can marry the Avatar's daughter, and the Avatar's son Kana can marry Azura's daughter. For bonus points [[spoiler: KissingCousins comes into play: the Avatar and Azura are cousins, meaning their children are second cousins to each other.]] ''Conquest'' and ''Revelation'' have a Double Subverted example: the Male Avatar can marry Flora and either Xander or Leo can marry her sister Felicia. Subverted in that the Avatar is not blood related to Xander and Leo. Double subverted in that the Avatar only learned this recently, and certainly still regards Xander and Leo as his brothers. The same Avatar/Flora pairing can also create a straighter version in ''Revelation'', as Ryoma and Takumi are also recruitable here and can be paired with Felicia. [[spoiler:"Straighter" in that it's only a single subversion, as Ryoma and Takumi aren't blood relatives of the Avatar either. However, this time the Avatar doesn't ''know'' that.]] ''Birthright'' also has a subverted example if the Female Avatar replaces one of the women in the above mentioned ninja example [[spoiler: for the same reason it's subverted with a Ryoma/Takumi example.]]

* Planned in ''Webcomic/{{Homestuck}}'': According to their destiny, Rose must marry John while her twin Dave must marry John's twin Jade. Whether this will actually come to pass, or whether they will fight fate remains to be seen, particularly since Rose is [[spoiler: already in a relationship with Kanaya.]] Note that "fate" here means "teenage alien [[ShipperOnDeck with a shipping grid]]", and the only reason he's bothering is because the kids are [[AdamAndEvePlot the last surviving humans]] [[spoiler: except for alternate-universe teenage versions of their parents.]]

* Averted in the case of the Dionne quintuplets (the first ever surviving set of quintuplets, all girls): Dr. Allan Roy Dafoe, who had charge of them through their tenth year, was convinced that they would never marry because there was no set of identical ''male'' quintuplets. Three did eventually marry men not related to one another; one became a nun (and died young, to boot); and the fifth devoted herself to her work and never married.
* Almost happened with UsefulNotes/NapoleonBonaparte and his elder brother Joseph : Joseph married Julie Clary, the daughter of a wealthy silk merchant, in 1794 and Napoleon fell in love with and became engaged to Désirée, Julie's younger sister. However, Désirée's parents did not want another Bonaparte son-in-law; instead, Napoleon met and married the attractive and influential widow Joséphine de Beauharnais, leaving Désirée to marry General Bernadotte and eventually become Queen of Sweden.
* On 24 and 26 December, 1793, Crown Prince Frederick William of Prussia (later King Frederick William III) and his next-eldest brother Ludwig (or Louis) married two sisters, Princesses Louise and Friederike of Mecklenburg-Strelitz. Frederick William married Louise, Louis married Friederike.
** Two of Frederick William's sons, William (later Kaiser Wilhem I) and Charles, also married sisters, with William marrying Augusta of Saxe-Weimar-Eisenach and Charles marrying her older sister Marie.

* In ''Anne's House of Dreams'', Leslie's husband Dick had a "double cousin" named George who looked almost like his twin. [[spoiler: When the brain-damaged man everyone had assumed was Dick for thirteen years was cured, it turned out to be George.]]

* In KingArthur mythology, brothers Gareth and Gaheris married sisters Lyonesse and Lynette (which way round depends which telling you read).

* In most versions of Gareth's story in [[Myth/KingArthur Arthurian Myth]], after he marries his DamselInDistress Lyonesse, her sister, the DamselErrant Lynette, falls in love with his brother Gaheris.

* The plot of ''Disney/MulanII'' starts when the Emperor has Mulan escort his three daughters to a neighboring kingdom to marry its ruler's three sons, as part of an alliance.

* In a [[Literature/TheLionKingSixNewAdventures series of books]] about ''Disney/TheLionKing'', Simba and Nala have a son, Kopa, thus making him Kiara's brother. Guess who Kovu's sister, Vitani, is almost always paired up with.

* Downplayed in ''Fanfic/SonOfTheSannin''. Naruto is dating Hinata while his cousin Karin ends up with Hinata's cousin Neji.

* This ''would'' have happened in ''Film/GoneWithTheWind'' if brother and sister Charles and Melanie Hamilton had married their cousins Honey and Ashley Wilkes, respectively, as had long been planned, in keeping with the family tradition of the Wills and Hamilton clans intermarrying. However, Scarlett O'Hara decided to interfere, and in a failed attempt at getting Ashley for herself or at least making him jealous, ''she'' ended up married to Charles.

** The characters had a lot of fun joking about David and Darlene's relationship after they essentially adopted him as a member of the family long before Becky got married. To the point where when Darlene and David get engaged Roseanne celebrates the fact that they are officially the most redneck white trash in town.
* In ''Series/LostInAusten'', after Mr. Collins marries Jane, he tries to marry his brothers off to the younger Bennett sisters. It doesn't quite work out.

* ''Series/MarriedWithChildren'': In "How to Marry a Moron", Kelly is engaged to a rich guy named Lonnie Tot and Lonnie's ugly sister is interested in Bud. When Lonnie's Dad says he'll make Al his business partner if both marriages take place, Al eagerly announces Bud's engagement.

* The Clothar race in ''TabletopGame/{{Traveller}}'' always has these. Clothar are born as a brother sister pair of mindlinked twins and each pair marries another pair creating what amounts to a quadruple marriage rather then a dual marriage. As each pair is telepathic, effectively everyone knows everything about the others marriage.

* Averted in the case of the Dionne quintuplets (the first ever surviving set of quintuplets, all girls): Dr. Allan Roy Dafoe, who had charge of them through their tenth year, was convinced that they would never marry because there was no set of identical ''male'' quintuplets. Three did eventually marry men not related to one another; one became a nun (and died young, to boot); one devoted herself to her work and never married.
* Almost happened with UsefulNotes/NapoleonBonaparte and his elder brother Joseph : Joseph married Julie Clary, the daughter of a wealthy silk merchant, in 1794 and Napoleon fell in love and became engaged with Désirée, Julie's younger sister. However, Désirée's parents did not want another Bonaparte son-in-law, Napoleon met and married the attractive and influential widow Joséphine de Beauharnais, leaving Désirée to marry General Bernadotte and eventually become queen of Sweden.

* Prince Harry and Pippa Middleton allegedly grew close during their siblings' wedding preparations (and the media jumped onboard), but nothing came of it, and both eventually married other people.
* Louis XIII of France married the Spanish princess Anne of Austria, while his sister Elisabeth married Anne's brother Philip IV of Spain. Their respective children Louis XIV of France and Maria Theresa of Spain later married each other, which meant that their child Louis, the Grand Dauphin had as many great-grandparents as grandparents.
* Twice over for the four beautiful daughters of Ramon Berenguer IV, Count of Provence: Marguerite and Beatrice married one set of brothers, Louis IX of France and Charles I of Naples and Sicily while Aliénor and Sanchia married another set of brothers, Henry III of England and Richard of Cornwall, King of the Romans. With the exception of Sanchia and Richard's, all of these were {{Perfectly Arranged Marriage}}s.

[[/folder]]
----

->'''Atticus:''' Double first cousin.
->'''Scout:''' How can that be?
->'''Atticus:''' Two sisters married two brothers.

[[folder:Film]]

* The plot of ''Disney/MulanII'' starts when the Emperor has Mulan escort his three daughters to a neighboring kingdom to marry its ruler's three sons, as part of an alliance.

[[folder:Religion & Mythology]]

[[folder:Web Video]]
* ''WebVideo/LiliumSims2'': Siblings Horitio and Isis are in {{Arranged Marriage}}s to another pair of siblings named Balatazar and Estella.
[[/folder]]

* Although it's only part of the act that they keep up to appear human, the Cullen/Hale "kids" ''appear'' as this to outsiders in the novel Twilight. Alice Cullen is with Jasper Hale while her "brother" Emmett Cullen is with Jasper's "sister" Rosalie Hale. It's implied that the family puts on some variety of this trope whenever they all move to a new location together, and that Bella and Edward will be folded into the deception now that they're together and both vampires.

-->''Literature/ToKillAMockingbird''

Bob and Carol are siblings. So are Alice and Dan. Alice marries Bob, while Carol falls in love with Dan. This would also work if Alice and Carol were sisters, and Bob and Dan were brothers. Then Alice would marry one brother, and Carol would marry the other. There are other QueerRomance variants.

In other words, it's any time a pair of siblings marry another pair of siblings. Someone marries the sibling of their own sibling's spouse.

This can lead to a major TangledFamilyTree as the children of one couple are "double cousins" of the children of the other. Since they are as genetically similar as quarter-siblings, KissingCousins is even more discouraged in such cases. This gets ramped up in cases of one or two sets of identical twins being involved, in which case the cousins are biologically as close as half-siblings (with one set) or full siblings (with two sets).

A popular way to resolve a SiblingTriangle. Compare BestFriendsInLaw, which only involves three people. Not to be confused with SettleForSibling, although overlap is certainly not impossible. Not at all the same as BrotherSisterIncest.

This can lead to a major TangledFamilyTree as the children of one couple are "double cousins" of the children of the other. Since they are as genetically similar as half-siblings, KissingCousins is even more discouraged in such cases. This gets ramped up in cases of one or two sets of identical twins being involved, in which case the cousins are biologically as close as half-siblings (with one set) or full siblings (with two sets).

* A Disney ''{{WesternAnimation/Silly Symphon|ies}}y'' ended like this. Two feuding royal families make peace, and the king and the prince of one kingdom marry respectively the queen and princess of the other kingdom (by the way, they were also all anthropomorphic musical instruments).

* ''Series/TheWhiteQueen'': As in RealLife, two York brothers, George of Clarence and Richard of Gloucester, are married to the two Neville sisters, Isabel and Anne, respectively. Cecily Neville, the mother of George and Richard, is thus both the mother-in-law and paternal great-aunt of Isabel and Anne.

[[folder:Comics]]

[[folder:Fan Fiction]]

[[folder:Webcomics]]

This can lead to a major TangledFamilyTree as the children of one couple are "double cousins" of the children of the other. Since they are as genetically similar as half-siblings, KissingCousins is even more discouraged in such cases. This gets ramped up in cases of one or two sets of identical twins being involved, in which case the cousins are biologically as close as full siblings.

[[folder:Live Action TV]]

* ''Series/TheWhiteQueen'': As in RealLife, two York brothers, George of Clarence and Richard of Gloucester, are married to the two Neville sisters, Isabel and Anne, respectively.