If you have one child and have ever been asked, “so, when is the next one coming?”, you probably already know the assumption behind the question. Only children, the thinking goes, are lonely. They are spoiled. They struggle to share, to get along, to cope with the real world. These ideas are often passed around so casually that they can sound less like opinions and more like settled fact.
But where did these beliefs actually come from? And more importantly, how well do they hold up now?
That question matters for more than academic reasons. Ideas about only children do not just shape how people talk. They shape what parents worry about, what families feel pressured to explain, and sometimes even the decisions people make about whether to have another child.
A stereotype with a very old history
The stigma around only children has a surprisingly specific origin. In 1896, the American psychologist G. Stanley Hall described being an only child as “a disease in itself.” It was a dramatic claim, and one that modern readers can immediately hear as extreme. The problem is that it did not remain an isolated remark. It helped build a wider cultural story about only children as selfish, fragile, odd, or somehow incomplete.
By today’s standards, Hall’s methods would not be considered scientifically rigorous. But the authority of psychology carried weight, and the idea stuck. For decades, it filtered into parenting advice, education, and everyday conversation. Once a stereotype becomes familiar enough, people stop hearing it as a stereotype at all. It starts to sound like common sense.
That long afterlife matters. Many of the assumptions people still make about only children today can be traced back to early ideas that were weakly grounded from the start.
What family life looks like now
Family structures have also changed a great deal, even if the cultural assumptions have not changed as quickly. Across the European Union, almost half of households with children have one child. In some countries, one-child families are not unusual at all; they are one of the most common family forms.
That shift is important because it changes the context of the discussion. When a family structure becomes this widespread, across different cultures and circumstances, it becomes harder to treat it as an obvious problem or a deviation from what family life is supposed to look like. In many cases, having one child is not an accident, a failure, or a temporary stage before the “real” family begins. It is the family.
And yet the old assumptions often remain. Parents of one child are still asked when the next one is coming, as if one could never be enough on its own. The script survives even when the demographic reality has changed.
What research says about only children
Over the past few decades, researchers have examined only children much more carefully than early writers like Hall ever did. One of the most widely cited reviews, by Toni Falbo and Denise Polit, found little evidence for the stereotype that only children are lonely, selfish, or maladjusted. Later research has pointed in much the same direction.
That does not mean every study says exactly the same thing, or that growing up without siblings is identical to growing up with them. But it does mean the old broad-brush claims do not stand up well. Personality differences between only children and those with siblings tend to be small, inconsistent, or absent on most measures. That is very different from the dramatic image many people still carry around.
One of the most persistent stereotypes is that only children are more self-centred or narcissistic. A later study on adults found no evidence that only children are more narcissistic than people who grew up with siblings. That matters because the narcissism claim is one of the most common modern versions of the older stereotype. It sounds contemporary, but it often repeats the same old suspicion in updated language.
Some studies do suggest that children without siblings may get less everyday practice in certain social situations at home, especially conflict resolution, compromise, and negotiating shared space. That is a reasonable point. But it is not the same as saying they are socially deficient. It points to a difference in environment, not a flaw in the child.
Children build social skills in many places. They learn through friendships, preschool, school, cousins, neighbours, clubs, routines, and the communities around them. Siblings are one context for social development, but they are not the only one, and they are not a guarantee of emotional maturity either.
Why the myths still have power
If the evidence is weaker than the stereotype suggests, why do the myths still hold on so tightly?
Part of the answer is that cultural beliefs often outlive the research that challenges them. The image of the lonely or spoiled only child is deeply familiar. It shows up in jokes, films, casual comments, and throwaway interpretations of other people’s behaviour. When a child seems shy, intense, or used to adult company, people may say, “Ah, that makes sense, he’s an only child,” as if the conclusion explains itself.
Another part of the problem is that older research was often taken far more universally than it should have been. Family life is shaped by culture, childcare systems, community life, economics, and parental support. What it means to grow up with or without siblings can look quite different depending on the wider environment around the child. Children are also individuals. Temperament, parenting style, stability, opportunity, and relationships all matter.
In other words, sibling status alone cannot carry the explanatory weight people often put on it.
The pressure these beliefs place on parents
This is where the conversation becomes more than theoretical. Myths about only children do not just influence how outsiders judge children. They can also influence how parents judge themselves.
Some people have more than one child because that is genuinely what they want. But others feel pulled by a quieter pressure: the worry that stopping at one will be seen as selfish, insufficient, or somehow unfair to the child they already have. It is not always said directly. Often it appears in assumptions, hints, jokes, or comments that make a second child sound inevitable.
I remember being in hospital shortly after giving birth, still finding my footing, and hearing several members of staff refer casually to “next time.” Not as a question. As a given. The assumption that there would be a second child was so automatic that it barely registered as an assumption at all.
That kind of certainty adds up. It creates a climate in which one child can seem like an incomplete answer, even when it may be the right and responsible choice for a family. But raising children well takes time, emotional capacity, energy, and stability. A family stretched beyond what it can realistically sustain does not automatically give a child more simply by becoming larger.
A more reasonable place to land
None of this means that growing up as an only child is exactly the same as growing up with siblings. It is not. Different family structures create different experiences, and those differences can be meaningful. But difference is not the same as damage.
What current research does not support is the long-standing claim that only children are inherently disadvantaged, selfish, lonely, or emotionally stunted. Those myths have lasted far longer than the evidence behind them.
For parents raising one child, or honestly wondering whether one is enough, that matters. It matters because decisions about family size are deeply personal, and they deserve to be made with more than inherited fear. At the very least, they deserve to be made with a clearer sense of what the evidence actually says.
Sources
Sources for this post are included below for readers who want to explore further.
- Falbo, Toni, and Denise F. Polit. 1986. “Quantitative Review of the Only Child Literature: Research Evidence and Theory Development.” Psychological Bulletin.
- Dufner, Michael, Mitja D. Back, Franz F. Oehme, and Stefan C. Schmukle. 2020. “The End of a Stereotype: Only Children Are Not More Narcissistic Than People With Siblings.” Social Psychological and Personality Science.
- Eurostat. 2020. “These Days, Are You at Home Alone or With Your Family?”
- BBC Worklife. 2022. “Why Only Children Are Still Stereotyped as Selfish and Spoilt.”
- Greater Good Magazine. 2023. “Debunking the Myths of the Only Child.”
