Our culture has something against one-child families. It’s nonsense

One of the weirdest pseudoscientific beliefs of the Victorian era to have persisted to the present is that, as G. Stanley Hall, the first president of the American Psychological Association, said, “to be an only child is a disease in itself.” Few people put it quite like that these days, but the idea hangs on that there is something wrong with being an only child—that it’s unfair or even abusive of parents not to “give” their first children siblings and that only children turn out somehow damaged, if not exactly diseased. According to a summer 2023 Gallup poll, just 3% of people say that one is the ideal number of children to have—and just 6% of people with one child say it’s the ideal. That’s framed in terms of “ideal,” but you don’t get numbers that low unless there’s a widespread cultural view that there’s something wrong with it.

Reality is different. There’s a lot of research comparing only children with people from multichild families. And while it’s certainly possible to cherry-pick studies finding headline-friendly differences (only children are more likely to get divorced, according to the headlines on a study finding that the likelihood of divorce drops by a whopping 2% with each additional sibling, up to around seven), studies in general find small differences, and there are conflicting results across studies. As demographer Alice Goisis, who has researched cognitive differences between only children and those with siblings, has written, “We found that only children’s cognitive development by age 11 is more affected by things like their parents’ relationship and their family’s socioeconomic status than whether they have brothers and sisters.” It seems very likely that most of the differences supposedly uncovered by other studies are similarly small compared with other factors.

Then there are the plausible outcomes of growing up in a world that believes there’s something wrong with you or your family structure. As Chiara Dello Joio wrote in The Atlantic in 2022, “It’s tough to distinguish inherent only-child qualities from those that develop in a sibling-centric world.” So this is where (and I’m only partly trolling here) I want to argue that it’s not just that the prejudice against only children and one-child families should go the way of other Victorian pseudoscience. No, we need to be more willing to acknowledge the largely unacknowledged problems with multichild families.