Recent studies have highlighted the effects that maternal stress during pregnancy can have on infants’ development. Now, researchers from the Max Planck Institute for Evolutionary Anthropology have found that having older siblings can lead to better behavior and stronger development in young children. The findings remained true even when children were exposed to their mothers’ stress in utero.
“In the first years of their lives, children develop the cognitive, social, and emotional skills that will provide the foundations for their lifelong health and achievements,” the researchers explained. “To increase their life prospects and reduce the long-term effects of early aversive conditions, it is therefore crucial to understand the risk factors that negatively affect child development and the factors that are instead beneficial.
“Overall, our results confirm the negative effects that maternal stress during pregnancy may have on the offspring, and suggest an important main effect of older siblings in promoting a positive child development.”
Benefits of siblings
The researchers had nearly 400 mother-child pairs answer questions about behavior, development, and stress. The team followed the women and their children from pregnancy until their children were 10 years old. They also took into account social and environmental factors that could affect stress levels and the role that siblings played on children’s developmental and behavioral outcomes.
The study showed that women who reported higher levels of stress during pregnancy were more likely to report that their children struggled with behavior once they reached seven years old. They found that many of the mothers reported feeling tense, worried, and experienced a loss of joy during pregnancy. Over time, this translated to poorer behavioral outcomes for their children.
“These results confirm previous findings about the negative impact that even mild forms of prenatal stress might have on child behavior, even after several years, and highlight the importance of early intervention policies that increase maternal well-being and reduce the risks of maternal stress already during pregnancy,” said researcher Federica Amici.
However, a positive takeaway from this study was that children who had older siblings were more likely to have better behavioral and developmental outcomes regardless of their mothers’ stress levels. The team explained that interactions with older siblings can give kids important social tools. These sibling social dynamics may also help improve kids’ emotional development and problem-solving skills.
“We were especially impressed by the important role that siblings appear to play for a healthy child development,” said researcher Anja Widdig. “We hope that our findings will draw attention to the importance of public health policies that directly target children and their siblings, and promote a healthy environment for their well-being and the development of high-quality sibling relationships.”