China’s One Child Policy has created millions of single children since the early 1980s, and controversies surrounding the mental health of these only children have persisted to this day. Even without clear evidence, older generations who grew up in larger families with siblings used to criticize these only children for being selfish, among other alleged faults, as they don’t have to share anything with siblings.
However, recent research conducted on both Chinese and American teens has discovered quite the opposite.
The study, published in Journal of Family Issues, finds that teens from larger families have poorer mental health than those with fewer or no siblings.
The way siblings are spaced apart and their ages can affect how they interact with each other. A study found that this pattern was seen in two different countries, which was surprising. According to the authors of the study, hail from Ohio State University, what’s truly remarkable about this discovery is that this pattern was observed in both countries with dramatically different culture. Earlier studies have shown that having more siblings can lead to positive outcomes, this makes the finding all the more unexpected and counterintuitive.
The study was conducted by analyzing data from over 9,400 eighth graders in China and over 9,100 eighth graders in the United States. The average Chinese youth has nearly one-half fewer siblings than the average American youth (0.89 compared to 1.6). This difference can be attributed to China’s One Child Policy, which has resulted in about one-third of Chinese children being only children (34%), compared to just 12.6% of American children.
In both countries, the researchers posed a range of questions to the students (average age 14) about their mental health, although the questions were customized for each country.
In China, teens without siblings exhibited the best mental health, while in the United States, those without or with only one sibling had comparable mental well-being.
Some aspects of the study could only be fully appreciated using data from the United States. The U.S. data revealed that half-siblings and full siblings are both associated with poorer mental health. Moreover, having older siblings or siblings born closely together was found to have the most negative impact on well-being. Specifically, having siblings born within one year of each other was most strongly associated with negative mental health outcomes.
The link between more siblings and poorer mental health remains a puzzle. Some experts believe this could be explained by the “resource dilution” theory, which posits that when parents have more children, each individual child receives fewer resources and attention, potentially impacting their mental well-being. Closely spaced siblings, in particular, seem to have the most negative impact, as they compete for the same parental resources.
However, it’s also possible that families with more children differ from those with fewer children in other ways that could affect their children’s mental health. In China and the United States, children from families associated with the most socioeconomic advantage had the best mental health. In China, this was children in one-child families, while in the U.S., it was children with zero or one sibling.
The authors emphasized that while the research shows a negative impact of siblings on mental health, the quality of sibling relationships may be more beneficial for children. Other research has shown that having more brothers and sisters is associated with better social skills among kindergarteners and a lower likelihood of divorce among adults.
The researchers acknowledge that these findings present a complex puzzle that is not easily deciphered. Furthermore, there is still much to be discovered regarding the influence of siblings on individuals.
In light of the declining fertility rates in countries such as China, the United States, and many others worldwide, comprehending the implications of growing up with fewer or no siblings has become an increasingly significant social concern.