[[quoteright:250:[[WesternAnimation/TheSimpsons http://static.tvtropes.org/pmwiki/pub/images/the_simpsons_250x365_2229.png]]]]
[[caption-width-right:250:There's also the family pets, but who's counting?]]

Or a Boy, a Girl, and Baby siblings. Not only are families with three kids common in TV land, but often they are made with a boy, a girl and a baby of either sex (nearly 50/50 ratio).

And that kind of family has immutable rules:
* The two elder siblings are very close in age, between one and three years. The eldest sibling can be either sex, but it is usually a girl. The odds of the oldest being a girl seem to go up with the size of the age gap between the two older siblings.
* On the opposite end of the scale, the youngest is far from them, between five and 14 years younger.
* The boy and girl are between ages 7 and 15 years: not too young children and not too old teens, either.
* The baby is not an infant: more like a toddler between six months and 2 years old, but too young to talk.
* Just because one can't walk or talk yet does not mean that the infant sibling is [[TheLoad good for nothing]] or powerless. On the contrary, the infant is often shown to be the most powerful in the family (if applicable), or a BrainyBaby, or a LittleMissBadass. Even when they are only the PluckyComicRelief for most of the story, the baby can save the day at the very end as the [[BigDamnHeroes Big Damn Hero]].

The reason? Brother and Sister have the target audience's age and allow everyone in the audience to identify with the sibling of the same gender. The baby could also be a substitute for a child while the siblings are "parents". It also allows the writers to have starring characters for AlwaysMale and AlwaysFemale plots or tropes, and the baby as a child substitute, a third man or younger sibling role. The sex of the baby varies as gender doesn't make as much of a difference for infant characters. Alternatively, the baby can take the role of a TeamPet.

See also SiblingTeam.
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!!Examples

[[AC:{{Anime}}]]
* Ken and Miyako's children, at the end of ''Anime/DigimonAdventure02''.

[[AC:{{Manga}}]]
* In the manga ''Kocchi Muite Miiko'', the Yamada family has Miiko, Mamoru, and their baby sister Momo.

[[AC:{{Fanfiction}}]]
* At the very end of the ''{{Superjail}}'' fanfic ''Fanfic/ExtendedStay'', the Warden and the Mistress's family has been established as this with their [[UntoUsASonandDaughterAreBorn mixed-gender twins]] Matilda and Ethan and the "baby" Edward. (Although at this point, the twins are twenty years old; their brother being about four years younger than them.)
** [[DreamingOfThingsToCome Foreshadowed earlier in a dream]] Mistress has in Chapter 11.
* ''FanFic/KyoshiRising'', Kyoshi is the youngest of three (her older sister being approximately nine years older), and also the only [[ElementalPowers Bender]] in the entire family (not to mention the latest incarnation of [[GodInHumanForm the Avatar]]).

[[AC:{{Film}} -- Animated]]
* Violet, Dash and Jack-Jack Parr in ''TheIncredibles''.
* Fievel, Tanya and Yasha Mouskewitz in ''WesternAnimation/AnAmericanTail''.
* [=LaShawn=], Kahlil, and Pee-wee in ''WesternAnimation/BebesKids''.
* Eep, Thunk, and Sandy in ''WesternAnimation/TheCroods''.
* Pacha and Chicha's children in ''TheEmperorsNewGroove'', even though the baby was only seen for a few brief seconds at the end of the film.

[[AC:{{Film}} -- Live-Action]]
* Pugsley, Wednesday and Pubert Addams in the second movie of ''Series/TheAddamsFamily''.
* Nick, Amy and Adam Szalinski in ''Film/HoneyIShrunkTheKids'' franchise (although they didn't appear together).
* In the short [=1950s=] film ''A Date With Your Family'' (seen on ''Series/MysteryScienceTheater3000''), the family in question included teenaged "Son" and "Daughter" and their little brother "Junior." They're an older variant on the trope; "Junior" is around eight.
* The Cooper Family from ''Film/AlexanderAndTheTerribleHorribleNoGoodVeryBadDay'' consists of two boys (Anthony and Alexander), a girl (Emily) and a baby (Trevor).

[[AC:{{Literature}}]]
* The Baudelaire siblings from ''Literature/ASeriesOfUnfortunateEvents''.
* The 10-year old twins Kestrel and Bowman Hath and their infant sister Pinto in ''The Wind Singer''. In the later books of ''The Wind On Fire'', the characters age.
* The Balicki family from ''The Silver Sword''.
* ''Literature/TheBerenstainBears'', at least since the addition of baby Honey Bear.
* Tash and Zak Arranda in ''Literature/GalaxyOfFear'' are being looked after, [[OrphansOrdeal with some difficulty]], by their uncle. When they find a baby they want to adopt him and make this, but [[spoiler: he's actually a {{Tykebomb}}.]]
* In the ''Flossie Teacake'' books by Hunter Davies, the title character has two siblings (a brother and sister) who are seven and nine years older than her. All three characters are based on the author's real-life children.
* In the children's boo ''Boundless Grace" by Mary Hoffman, Grace laments that she doesn't have a "real family" like in her stories with a Mom, Dad, brother, girl, baby, cat, and dog. A trip to Africa to visit her father, helps her understand that families take many different forms.
* Olivia, Ian, and William in ''Literature/{{Olivia}}''.

[[AC:LiveActionTV]]
* Robbie, Charlene and Baby Sinclair in ''Series/{{Dinosaurs}}''.
* ''Series/GoodLuckCharlie'' started out as a series with two boys (P.J. and Gabe), a girl (Teddy) and a baby (Charlie). As the series progressed, Charlie grew up and Toby was born, making it a series with two boys, two girls, and a baby.
* In the fourth season of ''Series/{{ALF}}'', the Tanner family consisted of this, with Lynn, Brian, and Eric.

[[AC:NewspaperComics]]
* Zoe, Hammie and Wren from ''ComicStrip/BabyBlues'', eventually.
* ''ComicStrip/ForBetterOrForWorse'', back when April was still a baby.
* For a short time after Rerun was born, there's Lucy, Linus and Rerun van Pelt in ''{{Peanuts}}''.
* The family from ''ComicStrip/FoxTrot'' would have followed this back when Jason was a baby (more or less -- Paige would have only been four or five), although we never get to see that time except in the rare FlashBack.

[[AC:VideoGames]]
* If you make it back to Funkotron at the end of ''VideoGame/ToejamAndEarl'', Toejam is revealed to have two younger twin sisters and a baby sibling in his family.

[[AC:{{Webcomics}}]]
* Holy, Polo and Elis in ''Webcomic/IrregularElis''.
* Riyuokoan, Mimi and Enigma in ''Webcomic/FiyoraNya''.
* Rudy, Lindesfarne and Coney Dewclaw of ''Webcomic/KevinAndKell''.

[[AC:WesternAnimation]]
* Bart, Lisa and Maggie Simpson in ''WesternAnimation/TheSimpsons''.
* Chris, Meg and [[EvilGenius Stewie Griffin]] in ''WesternAnimation/FamilyGuy''.
** Cleveland Jr., Roberta and Rollo in ''WesternAnimation/TheClevelandShow''.
* Arthur, DW and Baby Kate in ''WesternAnimation/{{Arthur}}'', although DW is only four years old, eventually aged up to five.
* Doug, Judy and Cleopatra "Dirtbike" Funnie in ''WesternAnimation/{{Doug}}'' when the last one was born in the Disney version. The episode "Doug's Thanksgiving" even lampshades this by having a PR exec scouting for the quintessential "average" family, which must have "2.5 children -- a boy, a girl, and a baby with a quirky name!" No points for guessing who he picks.
* ''WesternAnimation/PBAndJOtter'': Peanut (brother), Butter (baby sister) and Jelly Otter (sister). Another slight aversion from the normal rules - Baby Butter is old enough to talk a little at least, and while the ages aren't certain, she may be only about three or four years younger that Peanut and Jelly.
* ''WesternAnimation/TheLionhearts'' also plays this straight.
* ''WesternAnimation/{{Birdz}}'' too.
* Buzzbee and his familly on ''WesternAnimation/TheHive''
* Subverted in ''WesternAnimation/TheBuzzOnMaggie'' with two boys, a girl, and a baby.
* ''WesternAnimation/TheLegendOfKorra'', SequelSeries to ''WesternAnimation/AvatarTheLastAirbender'', reveals that Aang and Katara had three children together: Kya, Bumi, and the "baby" Tenzin.
** Averted with Tenzin's own family, however, since his two oldest are girls, Meelo is too old to be a baby anymore, and another (boy) baby arrives at the end of the first season.
* An animated series based on the Fisher-Price toys called "Little People" (one episode can be seen [[http://www.youtube.com/watch?v=JsChVrnN_Ao here]]) involved a family whose children were Timmy, Penny, and "Baby Sister," who apparently didn't get her own name.
* The Duff Family from the ''WesternAnimation/{{Tiny Toon Adventures}}'' episodes, "Take Elmyra Please" and "Grandma's Dead" consists of two girls (Amanda and Elmyra), a boy (Duncan) and a baby (aptly named "Baby").
* ''{{Peter Rabbit}}'' has this with Peter, Flopsy and Mopsy, and Cotton-Tail.
* In ''WesternAnimation/BobbysWorld'', from the fourth season onwards, the Generic Family consisted of a girl (Kelly), two boys (Derek and Bobby), and two babies (Jake and Al).
* The ''Jayce and the Wheeled Warriors'' episode "The Slaves of Adelbaren" contains a reversal of this trope, with the Lightning League encountering a teenaged girl whose much younger brother and sister are being held hostage by the Monster Minds.

[[AC:RealLife]]
* Depending on the birthrate, families like this are easy to find around the world.
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