| 2 min read | from American Psychological Association |

WASHINGTON — A child with more than one brother or sister is more likely to be the victim of sibling bullying than those with only one sibling, and firstborn children and older brothers tend to be the perpetrators, according to research published by the American Psychological Association. 

“Sibling bullying is the most frequent form of family violence and it is often seen as a normal part of growing up by parents and health professionals, but there is increasing evidence that it can have long-term consequences, like increased loneliness, delinquency and mental health problems,” said Dieter Wolke, PhD, of the University of Warwick and co-author of the study. It was published in the journal Developmental Psychology®.

Wolke and lead author, Slava Dantchev, BSc, also of the University of Warwick, wanted to understand the underlying causes of sibling bullying and examined the possible impact of family structure, parenting behaviors, early social experiences and a child’s temperament.

Approximately 28 percent of the children in the study were involved in sibling bullying and psychological abuse was the most common form. The majority of those children were found to be bully victims, meaning they bullied and were bullied, according to the study.

“Bullying occurs in situations where we cannot choose our peers, like in families,” said Wolke. “Siblings live in close quarters and the familiarity allows them to know what buttons to press to upset their brothers or sisters. This can go both ways and allows a child to be both a victim and a perpetrator of bullying.”

Family structure and gender were the strongest predictors of sibling bullying by middle childhood, according to the authors.

“Bullying was more likely to occur in families with three or more children and the eldest child or older brothers were more often the bullies,” said Dantchev. “Female children and younger children were more often targeted.”

Wolke and Dantchev believe bullying can happen in larger families because resources such as parental affection or attention and material goods are more limited.

“Despite our cultural differences, humans are still very biologically driven. A firstborn child will have their resources halved with the birth of a sibling, and even more so as more siblings are added to the family,” said Wolke. “This causes siblings to fight for those limited resources through dominance.”

Although the researchers investigated whether marital and socioeconomic status would be associated with more or less bullying, they did not find any evidence. 

“Sibling bullying does not discriminate. It occurs in wealthy families just as much as lower-income families and it occurs in single-parent households just as much as two-parent households,” said Wolke. 

These findings may be helpful to parents as they welcome new additions to their families, Wolke said.

“It will be important for parents to realize and understand that resource loss can affect an older child,” he said. “It is a good idea for parents to manage this from the beginning by spending quality time with their firstborn or older children and by involving them in caring for younger siblings.”  

Article: “Trouble in the Nest: Antecedents of Sibling Bullying Victimization and Perpetration” by Slava Dantchev, BSc, and Dieter Wolke, PhD, University of Warwick. Developmental Psychology. Published online Feb. 14, 2019.

Dieter Wolke, PhD, can be contacted by email.

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