Do children need siblings to ensure they grow up into decent human beings? The answer is yes, according to a notable bunch of Victorian-era psychologists, who carried out some of the first research into “only child syndrome”.

Leading US psychologist G Stanley Hall claimed, rather dramatically, that being an only child is a “disease in itself”.

Meanwhile, Hall’s protégé, EW Bohannon concluded from his own 1896 study that only children tend to be spoiled, selfish, self-obsessed, socially inept and oversensitive.

Research into only child families in China found no difference in altruistic behaviour between only children and children with siblings

As an only child myself, I feel obliged to take issue with these findings—although I could just be oversensitive, of course.

Still, I’m pleased to note that both public and scientific opinion have evolved over the past 100 years, not least because the number of one-child families has pretty much exploded since Victorian times. In 2019, nearly half of all UK families with children—42.7 per cent, to be precise—had just one child.

Of course, this figure includes families who may go on to have more children. However, factors such as delayed parenthood, fertility issues and readily available contraception, as well as relationship and financial pressures, have resulted in an ever-increasing number of children growing up without siblings.

Surely we can’t all be selfish and awkward, can we?

In 2019, German researchers set out to shatter the stereotype that only children are more narcissistic than those from larger families.

They began by demonstrating how people tend to ascribe higher levels of narcissism to children with no brothers or sisters. The team then looked at various measures of narcissism from a study of German households, which featured 1,810 participants, including 233 without siblings.

Their findings? There was no difference in narcissism levels between those with and without siblings. Myth debunked!

Much of the recent research in this area has focused on only children in China, largely in response to the country’s one-child policy. Last year saw another myth debunked as researchers at Shaanxi Normal University in Xi'an investigated levels of selfishness within one-child families.

Participants were first asked to share their views on levels of altruism among only children and those with siblings, based on their own preconceptions. Unsurprisingly, only children were regarded as more likely to be selfish.

But when a second group was asked to rate themselves on altruism, and a further group was observed putting altruism into practice, there was no difference whatsoever between those with siblings and those without.

The researchers' conclusion? “The negative stereotype regarding the altruistic behaviour of only children is an incorrect prejudice.”

One study found that only children have more grey matter in their brains, which helps with creativity

Putting those negative preconceptions aside, there may be some clear benefits to being an only child.

Only children are more likely to enjoy a stronger bond with their parents, according to a University of Texas study. It’s fair to surmise that the more children you have, the less time you have to focus on each one—so these findings probably aren’t too much of a surprise.

But research has uncovered some other unexpected positives to being an only child. For instance, scientists at China’s Southwest University used brain scans to uncover significant differences in grey matter between only children and those who’d grown up with siblings.

Only children demonstrated greater brain “flexibility”, a key player in both learning and creativity, which was backed up by creative tasks completed as part of the study.

One potential downside to being an only child is that you don’t have anyone to share familial responsibilities, such as caring for ageing parents.

A few years ago, when my father was terminally ill, I wished I had a brother or sister who could share the workload and help me make the right decisions about his care.

Having spoken to friends with siblings, however, it seems it never quite works out that way. Arguments flare up, other commitments get in the way, and one person inevitably ends up shouldering most of the workload anyway.

Still, there’s plenty of research—scientific and anecdotal—that highlights the benefits of sibling relationships.

A University of Ulster and DeMontfort University study, for example, found that children who grow up with sisters are more likely to be happy and balanced, partly because families with daughters tend to be more open and emotionally available.

Ultimately, our happiness and successes in life are shaped by many environmental, social and psychological factors. Despite what those Victorian psychologists may have believed, being an only child is not a disease. It’s just one piece in an enormous jigsaw.

Read more: How having a sibling can improve your health

Read more: 10 Tips for raising happy, responsible children

Keep up with the top stories from Reader's Digest by subscribing to our weekly newsletter