I know that you mentioned in the show that you had two sets of twins but did you have two sets of triplets as well? A: In a recent episode of Sesame Street, a mother explained that she had twins that were not identical and then had two sets of triplets. A: Yes, in Sesame Street (season 21, episode 14, "Daddy Turns 50"): [Mum says that] she was expecting to get triplets from her twins but got two sets of triplets. [Dad says that] he once had triplets and that the third was the girl. [Mr. Snuffleupagus says] they were triplets too and one turned into a girl. A: There is a very obscure segment of the Simpsons that I can recall which was based off this concept. It is an Easter special featuring Hank Azaria as Moe when his wife gives birth to quadruplets. However, due to a mix-up in the hospital he ended up getting some of them instead. All four twins end up together in one cot and the fifth is a boy which is an only child. The twins are called Kevin and Wayne. If you want to get technical about it this is because Wayne's mother was already a twin of some kind and he turned out to be a girl. In the episode Homer the Mascot Homer gets the flu in a carnival and takes his shirt off. The crowd then starts calling for Mr. Nudelman because he's a dead ringer for him. He then proceeds to have four babies, even though he hasn't got a girl partner yet. The one that is clearly the youngest is called David, the one that looks just like him is called Jason and the one that looks like Apu is called Andrew. I remember being confused by this because at the time I wasn't aware that some people had multiples in their family. Although I was aware of identical twins but I wasn't aware that there was more than one definition of the word. I don't recall this ever getting explained in any form or fashion. In the episode Simpson Mafia it features Apu's son Apu Jr who has triplet sisters. The first daughter is called Pumi, the second (most likely the daughter that doesn't appear in the episode) is called Kumi and the third is called Akemi. This one confused me for a while but I eventually remembered that I had once encountered a similar situation. This occurred in an episode of the show Friends where Ross had twins, Phoebe and Rachel had triplets and Chandler had quadruplets. The twins were named Tara and Tom which I considered to be strange since in reality Tara and Tom's names would be male versions of each other. However, after a bit of research I found that both of these names are female variants of names that are considered male names. I then looked up the twin girls and found out that they are named Kirsten and Kandice. This was the first and last time I have ever seen or heard these names. The third set were triplets and their names were Ross, Rachael and Roman. Ross I had already encountered in the first story. My point is that even though there are some weird names that the show pulls off, it may confuse you when it is explained to you because you are not used to seeing these combinations. It's like I was back in 3rd grade when I first saw this episode and I wasn't sure if my classmate had a cousin called Kirsten because she liked to make up names. Hope this answers your question! Edit: As was pointed out by Cyrus in the comments, the show is also based on This Is Spinal Tap. So basically if you ever listen to an episode, try to watch Spinal Tap and notice that all of the names appear in real life. This is because the actors are all familiar with each other from working together on the sketch comedy show that the show is based off. A: Not an official answer, but another instance from the Simpsons was when Lisa became pregnant. In "Lisa's Pony", she was told she would be carrying quadruplets, even though two of them turned out to be boys. She decided she didn't want quadruplets at all and went to a fertility clinic who said she could use a fertility procedure that increased the chances of her having a girl. In "The Springfield Connection" the kids ended up being triplets. There are probably lots more examples, but I couldn't find any off the top of my head. EDIT: You're probably looking for the episode in which Lisa becomes pregnant with quadruplets and they turn out to be triplets. I've actually been searching for that episode because I have a twin sister and I'm trying to find out what her chances would be of having triplets, but haven't been able to find it. I believe it aired in 1992.