Only children are often seen as having the best of both worlds. Not only do they get all of their parents attention and love, they also don't have annoying younger siblings to take care of or bossy older siblings to listen to. However, this isn't always the case. Just like middle children, only children have their own complexities and stereotypes.
In fiction, only children are often portrayed as never having to compete with anyone else for parental attention or never having learned to live or communicate (in the worst cases) with others their age. They may also be spoiled by their parents. As such, only children are often portrayed as haughty, self-absorbed, or lonely, although this trope covers any behavior that the narrative ascribes to being an only child.
All this is in spite of the fact that it has been repeatedly shown in scientific studies that there is no measurable difference in the personalities of only children compared to those with siblings (at least not most of the time — there are a lot of perfectionists in the only child world). Only children also tend to mature faster.
See also Siblings Wanted, when an only child wants siblings. Compare and contrast Middle Child Syndrome. Compare Infant Sibling Jealousy: The former only child now has to compete with the baby for attention.
- Don't Toy with Me, Miss Nagatoro: Senpai is the only child in his family, which may have been a factor that contributed to his isolation.
- The Discworld of A.A. Pessimal sees two only daughters, each born to Grand Ducal families in what is left of the Discworld's Russia after its version of Soviet Collapse. Olga Romanoff and Natasha Romanoff are cousins. If they agree on one thing, it is that as only children they were deprived of a chance to fight The Glorious War of Sisterly Rivalry with an actual sibling. Therefore they have no choice other than to fight at one step removed, as cousins.
- Adam (2009): Beth tells her Dad that she must scare people off because of being an only child.
- Oceans 8: When self-absorbed actress Daphne admits that she wants to join the crew because she's lonely, Debbie asks if she's an only child. Her hesitant face suggests that she is.
- The Swap: Ellie has no siblings shown in the movie, which is probably why her mom is so protective of her.
- This Is Where I Leave You: Penny confesses that she can't really relate to the Altman's various hang-ups because she's an only child. Judd thinks that sounds wonderful.
- The Babysitters Club: Stacey is an only child, and it shows during the books where she and Mary Anne accompany the Pike family on their summer vacations to Sea City. It's very obvious that she's used to not having to show consideration for siblings, as she keeps prioritizing her own plans over Mary Anne's and even over minding the children. Incidentally, Mary Anne is also an only child (until her father marries Dawn's mother partway through the series), but averts the trope; the fact that she had only one parent and that parent was quite strict and is implied not to have been around as much due to a demanding work schedule is likely the reason for this.
- In The Berenstain Bears and the Trouble with Friends, Sister Bear befriends Lizzy Bruin, an only cub who means well but tends to to be "bossy and braggy." Her friendship with Sister helps her learn to share and compromise. Later in the series, however, she was retconned to have an older brother, Barry Bruin.
- In Earth's Children, Broud is the only child Brun and Ebra ever had. As a result, they both doted on him (Ebra especially), and Brun invested a lot of time and energy trying to make Broud a good future leader, seeing as he was the only one of Brun's line who could inherit the position (Brun's brother Creb never had children, Iza had only daughters whom she trained as medicine women). Unfortunately, it's implied that Broud never having to share his parents' attention with siblings, his mother's overindulgence and his father's lofty expectations, all contributed to him becoming a selfish egotist who cares more about his own status than the needs of others.
- The Elenium takes a humorous twist to the "never had to compete" bit mentioned in the trope description. Patriarch Bergsten is big and impressive note because he was an only child and didn't have to worry about sharing food with other siblings.
- Fiery Secrets: Grace is an only child and carries some stereotypical characteristics, such as being bossy and a perfectionist.
- In Harry Potter, Word of God suggests that James (the title character's father) owed his flippant and at times arrogant personality to being an only child, specifically one born late in the lives of rich parents. It's worth noting that Draco Malfoy and Dudley have similar backgrounds.
- Sherlock Holmes: "The Sussex Vampire" has a young boy deal very badly with the birth of his half-brother to the point of trying to murder him with a curare dart, even more so when the baby is perfectly healthy when the older one has a spinal injury.
- What Maisie Knew: Maisie's parents arguing doesn't help her socially as she has no siblings to either converse or interact with and is forced to overhear what her mom and dad say.
- In You Don't Own Me, the murder victim Martin Bell was his parents' only child, born unexpectedly when they were in their early forties and had given up hope of having children. As such, Cynthia and Robert regarded Martin as their "miracle child" and doted upon him. Unfortunately, it's implied their indulgence and belief he could do no wrong blinded them to Martin's flaws and swelled his ego to an unhealthy degree.
- Charmed (1998): Paige grew up as an only child and did not take well early on to moving in with her newly-discovered sisters and dedicating herself to becoming a Charmed One. She got used to it after her past life destroyed her loft.
- This is discussed in an interesting way in Everybody Hates Chris. Chris is jealous of Greg when he comes to stay with them because he's an only child and he expects all of the attention and does everything by himself, whereas Chris usually has to take care of his younger siblings. Near the end of the episode, Chris confronts Greg, and Greg says that the reason why he does everything by himself is not that he wants to, but because he has to, being an only child.
- Girls5eva: Scott and Dawn's plan to have a second son is hampered by Dawn's desire to have a Career Resurrection, and Scott worries that their son Max will be "weird" without siblings. Other characters reassure her that Max will be fine; he'll just grow up to be an Adorably Precocious Child.
- Misfits: Nathan fits the self-centered Attention Whore stereotype to a T- he lampshades it when he's asked if he has any siblings and responds "Have you met me? Classic only child." Although it turns out he has a half-brother he never knew about.
- New Girl: Schmidt's mother micromanaged the hell out of his childhood since he was her only son and now he's a micromanager himself. By contrast, his roommates all have siblings and are not nearly as uppity.
- Power Rangers Ninja Storm: In "Down and Dirty", seeing Hunter and Blake constantly arguing, Cam remarks he's glad he's an only child.
- Roseanne: DJ spends increasing amounts of time with his cousin Andy, much to Fred and Jackie's increasing annoyance, until he explains why. Just about everyone else in the cast had a brother or sister to grow up with, so DJ acts like a brother to Andy so he can know what it's like instead of being alone.
- Harry Kim from Star Trek: Voyager is an only child, and he once talks about how much his parents spoiled him, calling him their "miracle child". He often wondered if he really deserved that much devotion.
- Stuck in the Middle: Harley's best friend, Ellie, is an only child and also has a very overprotective mother.
- The Young Ones: In "Nasty", Vyvyan scoffs at Rick's claim of having a sister, pointing out that the arrogant, self-centered student is "the classic example of an only child".
- In Bill Cosby Himself, Cosby did a sketch on raising children. As part of this, he doesn't think that parents with only one child should be considered parents because too many things are left out.
"For instance, if something's broken in the house, you have only one child, you know who did it! See, you don't have to go through, 'I...I...I...' You know the child did it! Also, people with only one child does not have to go through 'Will you stop touching me! Will you stop touching me!' I mean, if you got one child and the child is doing that, then you gotta take it away."
- Clyde from The Loud House is an only child, and on a show focused on a family of 13, it shows. He's neurotic, overly cautious, and overly doted-upon.
- My Little Pony: Friendship Is Magic:
- Rainbow Dash can't bear being near her parents because they give her too much attention as their only daughter, as shown in "Parental Glideance". They are just proud of her accomplishments, but they can't stop bragging about her in public.
- In the season six episode, "Top Bolt", the Pegasus Vapor Trail was an only child whose parents piled attention on her, barely giving her a second to herself. Because of this, Vapor Trail developed an aversion to being in the spotlight, and was content with acting as the "wing pony" to her best friend Sky Stinger.
- Rugrats (1991): Angelica is an only child (notable because all the other kids in the main cast have siblings), and a Bratty Half-Pint with a massive ego due to being spoiled rotten by her parents. In the episode, "Angelica's Worst Nightmare", Angelica has a nightmare about her parents having another baby and forgetting about her. In another episode, "The Unfair Pair", Angelica convinces the twins that in families with only children, said only child is their favorite, and such is the case with her, Tommy, and Chuckie.note
- South Park: Eric Cartman is the only one of the four main boys who's an only child. He's also a narcissistic Spoiled Brat because his mother never says "no" to him, who has no idea how to work with other people unless he gets to boss them around and can't believe that the world doesn't revolve around him. Additionally, while he's very emotionally immature, he often shows a desire to be seen as an adult, chastising his friends as immature in "Cartman Joins NAMBLA" and killing all his toys in a symbolic effort to grow up in "1%."
- In real life, there were concerns that China's "One Child Policy" would lead to what was termed "Little Emperor Syndrome" (that is, the effect of having an entire nation of spoiled only children); however, it seems that such fears were largely unfounded.