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Feeling overwhelmed by your siblings? You’re not alone. A new study published in the Journal of Family Issues suggests that having more brothers and sisters might be linked to poorer mental health in teens, though it’s not quite that simple. Researchers analyzed responses from over 18,000 eighth graders in China and the U.S., and found that in both countries, kids with zero or just one sibling tended to report better mental health than those in bigger families.
Curious how birth order and family size might shape your teen years? Click through the gallery to see what the research reveals.
A new study suggests that teens growing up in larger families in the US and China may face more challenges when it comes to coping with everyday stress and emotional ups and downs.
Doug Downey, lead author of the study and sociology professor at Ohio State, found it striking that the same pattern appeared in both the US and China, highlighting a shared link between sibling count and adolescent mental health.
The study included data from over 9,400 eighth graders in China, collected through the China Education Panel Study, and more than 9,100 American eighth graders from the Early Childhood Longitudinal Study, offering a broad cross-cultural perspective.
“Our results were not what we expected,” said Downey. While other studies suggest that having more siblings can have positive effects, this study reveals a surprising connection between more siblings and poorer mental health.
In China, teens with no siblings reported the best mental health, according to the study.
In the US, teens with no siblings or just one sibling showed similar mental health outcomes, confirming that small family sizes can indeed positively impact adolescent well-being.
As expected due to China’s One-Child Policy, about 34% of Chinese children are only children, significantly higher than the 12.6% of American kids, reflecting the different family structures in the two countries.
In both China and the US, researchers surveyed students around 14 years old about their mental health, though the questions varied between the two countries, allowing for a tailored analysis.
Downey links the findings to “resource dilution”—the idea that parental attention is like a pie. With one child, they get the whole thing, but with more kids, that pie is sliced thinner, leaving each with less.
Downey explains that it’s simple math: more siblings mean less individual attention and fewer resources from parents, which can take a toll on a child’s mental health.
Tané Ruffin, a mom of six, shared that her 16-year-old and 12-year-old both agreed that resource dilution is a regular experience in their family, echoing the study’s findings about the challenges of growing up in larger households.
Ruffin’s kids confirmed the study hits home. One shared that she often holds back personal issues if mom’s already stressed with another sibling, which is a perfect example of how big families can stretch emotional airtime thin.
When asked how her teens might score on the study’s mental health questions, Ruffin guessed they’d rate themselves lower, but she questioned the measures themselves, suggesting they reflect confidence more than true mental wellbeing.
Samantha Quigneaux, the national director of family therapy services at Newport Healthcare, notes that with more children comes more competition for parental time.
When attention feels inconsistent or lacking, kids may feel neglected, which is a potential trigger for mental health struggles.
Quigneaux adds that not every child fits the trend; some kids thrive just fine without constant parental attention, showing that individual temperament also plays a big role in mental well-being.
Psychologist Jeff Gardere points out that siblings close in age may still have very different emotional needs, but parents often treat them the same, overlooking those unique differences.
While the study links more siblings with lower teen mental health, it doesn’t explore how sibling relationships actually play out. A loving bond could make all the difference!
Downey notes that strong sibling bonds can actually boost mental health, reminding us that it’s not just the number of siblings—it’s the quality of the relationship that counts.
Another factor at play? Teens with better mental health often came from wealthier families, suggesting that socioeconomic advantages might cushion the challenges of growing up with more siblings.
In both countries, smaller families tended to be wealthier. In the US, that meant one or two kids; in China, it usually meant just one, adding another layer to why these children reported better mental health.
Not all research agrees. A 2016 study from Norway, reported by The Guardian, found that kids from larger families actually had better mental health, suggesting culture and context make a big difference.
Downey’s earlier research also showed that kids with more siblings often had stronger friendships at school. This suggests that the link between sibling count and mental health can vary, depending on social connections.
Kids from bigger families might be less likely to divorce later in life, possibly because growing up with siblings gives them early practice in managing close, sometimes tricky relationships.
Geremy Keeton of Focus on the Family says teens may not see the perks of big families until later in life. “One study is just that—one study,” he noted, urging people to view it as just one piece of a larger puzzle.
Downey emphasized that because the study focused on teens, the lasting impact of siblings on mental health is still “an open question” for future research.
Downey shared a personal note: growing up with two older brothers was challenging at times, but he now considers them great friends. “Fortunately,” he added, “no one struggled with mental health.”
With families shrinking and only-child households on the rise, understanding how sibling count shapes our mental health isn’t just academic; it’s a growing social question that could define the next generation’s emotional well-being.
Sources: (The Guardian) (Ohio State News) (WORLD) (Deseret News)
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HEALTH Family
Feeling overwhelmed by your siblings? You’re not alone. A new study published in the Journal of Family Issues suggests that having more brothers and sisters might be linked to poorer mental health in teens, though it’s not quite that simple. Researchers analyzed responses from over 18,000 eighth graders in China and the US, and found that in both countries, kids with zero or just one sibling tended to report better mental health than those in bigger families.
Curious how birth order and family size might shape your teen years? Click through the gallery to see what the research reveals.