People with more brothers and sisters are less likely to divorce than only children or those with one or two siblings, suggests a new study that looks at the effect siblings may have on divorce in adulthood.
Each additional sibling a person has (up to about seven) reduces the likelihood of divorce by 2%, finds the analysis, based on data from 57,061 adults in the General Social Survey, collected between 1972 and 2012.
"There are a lot of other factors that affect divorce that are more important than how many siblings you had. However, we're finding that the number of siblings is a factor," says Ohio State University sociologist Doug Downey, a co-author of the study. It is being presented Tuesday at a meeting of the American Sociological Association in New York City. "Each additional sibling reduces their chances of divorce a little bit."
The authors suggest that siblings further the development of social skills useful in navigating marriage.
However, others who study divorce and family size say the study — while interesting — is far from definitive.
People from large families may be more family oriented, says sociologist S. Philip Morgan, director of the Carolina Population Center at the University of North Carolina-Chapel Hill. He says the data from the General Social Survey are "somewhat problematic" for the issue of divorce.
"I'm not yet convinced." he says. "The theory is interesting and plausible but not overpowering."
Demographer Paul Amato of Pennsylvania State University in University Park, Pa., agrees that the premise is "an interesting idea."
"It's the first study I know of to have looked at this, but in the social sciences, you shouldn't get too excited about a single study," he says. "It would have to be replicated multiple times before you can have too much faith in it."
Although this research doesn't suggest that only children should worry about their marriages, Morgan says he's not sure the underlying theory is correct — that only children are at a disadvantage.
"We're not in the 1950s, where (an only child) might live in a household and mom might stay home and you'd interact all day with an adult. No kids do that anymore," he says. "There are lots of opportunities to gain interpersonal skills."
A study of only children and adult sociability published two years ago in the Journal of Family Issues found that "adults who grew up without siblings do not appear to be different from others in their patterns or frequency of interaction across a wide variety of social interactions, such as with neighbors and coworkers. Nor do adults who grew up without siblings differ from others in their engagement in other social activities … Thus, in this study we find little evidence of long-term effects of growing up without siblings."
Lauren Sandler, 38, of Brooklyn, N.Y., an only child and the mother of a 5-year-old daughter, says school is the "great equalizer."
"As much as the culture would tell us we need to have siblings to learn how to manage conflict, all the data actually tell us that school does that just fine," says Sandler, author of the book One and Only, out earlier this summer. "Unless you're raising only children in a situation away from other kids, they will learn those skills with friends and classmates throughout their lives."