Some Curious Facts About Only Children

To what extent are the stereotypes about only children true? What does science have to say on the subject? Find out here.
Some Curious Facts About Only Children
Sergio De Dios González

Written and verified by the psychologist Sergio De Dios González.

Last update: 17 September, 2022

Until only about four or five decades ago, only children were a rarity. Most families took the Bible’s advice seriously to “be fruitful and multiply.” In fact, it didn’t seem to make much sense to build a family and only have one child. This led to the creation of a series of prejudices around them.

However, due to economic and social factors, and in particular to changes in the role of women, the trend is reversing. Consequently, whereas only children used to be the exception, now they’re more the rule. Indeed, it’s believed that up to 40 percent of households in the world today have only one child.

It’s also been shown that the higher the cultural and social level of the parents,  the fewer the number of children they have. This gives a slight advantage to only children, who tend to enjoy more stimulation and a more stable socioeconomic position. Let’s take a look at some more curious facts about them.

“Educate the children and it won’t be necessary to punish the men.”


Father and son talking happily
Questions can act as a bridge between you and your child. They give you the possibility of establishing close communication and a sincere bond.

Their brains develop differently

A study conducted by the University of China and published in the journal, Brain Imaging and Behavior found that only children may have different brain development than children with siblings.

The research examined 303 students, of which 170 were only children. All underwent psychological and psycho-technical tests, as well as MRIs to study their brains. They discovered that only children had more gray matter in the parietal lobe.

This was associated with greater mental agility, planning, and language ability. They also seemed to enjoy more creativity and imagination. On the other hand, they were more dependent and had fewer social skills than those who’d grown up with siblings.

The study indicated that children who grow up alone must be more imaginative and active when playing. That’s because they don’t have playmates which leads them to further develop their creativity. Also, since they interact less with other children and more with adults, this seems to give them a linguistic advantage.

Other studies

A few decades ago, only children were seen as a problem. It was thought that they were badly behaved and hence extremely difficult to educate. So much so that an association for the defense of parents of only children was even created. It was called Zero Growth and it sought to help parents ‘get the little ones on track’.

Thanks to the same organization, studies began to be conducted in various parts of the world. Indeed, science began to provide data that showed how wrong this perception was. They gradually collected evidence that indicated that only children were certainly different from those with siblings, but they didn’t coincide with the stereotypical idea.

In 2017, a study was published that claimed that, as a rule, only children tend to be more intelligent and also have better relationships with their parents than children with siblings.

The study also found that they tend to resemble their parents more than those who grow up in a family with many children. That’s because the interaction is more intense and focused. These little ones don’t have the possible models that siblings could offer them, but only the ones that their parents offer them. Hence, the identification is more direct.

Mother talking to her little daughter, representing that only children are on the increase.

Other curious facts

In reality, if only children had problems, there wouldn’t be so many of them who’ve grown up to be famous. Among them are such prominent figures as Leonardo Da Vinci, Albert Einstein, Jean-Paul Sartre, Franklin Delano Roosevelt, and Charles Lindbergh, among others.

Without going too far, 20 of the first 23 astronauts sent into space were only children. So were a host of entertainment figures such as Marilyn Monroe, Al Pacino, and Brooke Shields. Others include Leonardo DiCaprio, Robert De Niro, and Alicia Keys.

Of course, there are also many famous figures and celebrities who grew up with siblings. The truth is that there doesn’t seem to be any radical difference between having a family in which there’s only one child and another in which there are many. It seems that it’s genetics, parenting style, and personal experiences that shape each individual.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Villalobos, C. D. A., & Mondragón, L. E. C. (2017). Autoconcepto y habilidades sociales en niños como hijos únicos y niños con hermanos. PsicoEducativa: reflexiones y propuestas, 3(5), 38-44.
  • Yang, J., Hou, X., Wei, D. et al. Hijo único y no hijo único exhiben diferencias en creatividad y amabilidad: evidencia de estudios estructurales anatómicos y de comportamiento. Imágenes cerebrales y comportamiento 11 , 493–502 (2017).

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.