A bullying study led by Jenkins Tucker, an associate professor of family studies at the University of New Hampshire, shows that sibling bullying may cause deep psychological scars that could lead to mental health problems such as depression and anxiety.
According to the study, people who grow up being bullied by their siblings are linked to significantly worse mental health problems than people who aren't bullied.
"Even kids who reported just one instance had more mental health distress," said Tucker. "Our study shows that sibling aggression is not benign for children and adolescents, regardless of how severe or frequent."
Researchers analyzed data from telephone interviews with about 3,600 children ages 10 to 17 as well as adult caregivers of children 9 or under. The subjects had at least one sibling under the age of 18 who lived at home with them. The information was provided by the National Survey of Children's Exposure to Violence.
During the interview, the subjects were asked if they had been bullied by a sibling within the year. Researchers defined bullying as physical assault, property victimization or psychological aggression. In addition, subjects were asked if they had experienced anger, depression or anxiety in the previous month.
Results showed that eight percent of the children had experienced two or more types of bullying. Moreover researchers discovered that subjects that had been physically assaulted by a sibling exposed greater mental distress than those who weren't assaulted.
According to Tucker, parents often underestimate the effects of sibling bullying.
"There is a natural emotional intensity to sibling relationships. There is a lot of love, but also the potential for a lot of conflicts.
"Our work is showing that in some cases, the mental distress associated with sibling aggression is similar to what we see with peer aggression. It is something to be taken seriously," she added.
Tucker stressed that the objective of the study was not to blame the parents for what has happened, but to encourage them to do something about it.
"There is a big push now to stop aggression, particularly between peers, and we are suggesting that these programs include a focus on siblings," she said.