Study: Sibling Bullying as Bad as Peer Bullying

Sibling aggression can cause mental health problems in children that are just as bad as problems brought on by peer aggression, a new study finds.

The study was conducted at the University of New Hampshire and found that sibling aggression is linked to mental health problems in children and adolescents and that the effects were comparable to the mental health side issues normally associated with aggression from peers.

"Even kids who reported just one instance had more mental health distress," wrote Corinna Jenkins Tucker, associate professor of family studies at UNH and lead researcher of the study that was published in the July 2013 issue of the journal Pediatrics. "Our study shows that sibling aggression is not benign for children and adolescents, regardless of how severe or frequent."

The study examined the effects of physical assault, stealing, or breaking the property of another sibling on purpose, and psychological aggression such as verbal abuse that made a sibling feel bad, scared, or unwanted.

Researchers looked at children across a wide age and geographic range. The study is considered unmatched by its breadth of data. Tucker and two other researchers from the UNH's Crimes Against Children Research Center analyzed data from the center's National Survey of Children's Exposure to Violence, which is a national sample of 3,599 children from age 1 month through 17 years old.

The study found that the mental health distress caused by mild physical assault from a sibling was 32 percent greater among children ages 1 month to 9 years old, than for adolescents from ages 10 to 17 years old. However, psychological and property aggression had similar results.

According to the researchers, bullying from peers is generally believed to be more severe than similar physical and psychological aggression from siblings, but they say there was no difference in the psychological effects the aggression had on the children in their study.

They also warn parents against treating aggression from siblings more mildly than they would from peers.

"If siblings hit each other, there's a much different reaction than if that happened between peers," Tucker explains. "It's often dismissed, seen as something that's normal or harmless. Some parents even think it's beneficial, as good training for dealing with conflict and aggression in other relationships."

The researchers are encouraging pediatricians across the country to educate parents on their findings.