Siblings have been bickering and trading blows since the time of Cain and Abel. But the torment and fighting that is often shrugged off as normal sibling rivalry may not always be so benign.
New research suggests that even when there are no physical scars, aggression between siblings can inflict psychological wounds as damaging as the anguish caused by bullies at school. The findings offer an unusual look at an area of family life that has rarely been studied, in part because infighting among brothers and sisters is widely considered a harmless rite of passage.
Ordinary skirmishes are one thing, experts say, and chronic physical and verbal abuse is another. The new study, which involved 3,600 children and adolescents around the country, found that those who were attacked, threatened or intimidated by a sibling had increased levels of depression, anger and anxiety.
Corinna Jenkins Tucker, the lead author of the study, which was published in the journal Pediatrics, said that behaviors among siblings that cross the line into abuse deserve more recognition.
While normal rivalries with siblings can encourage healthy competition, the line between healthy relations and abuse is crossed when one child is consistently the victim of another and the aggression is intended to cause harm and humiliation, said John V. Caffaro, a clinical psychologist and the author of “Sibling Abuse Trauma.” Parents who fail to intervene, play favorites or give their children labels can inadvertently encourage conflict.
Nationwide, sibling violence is by far the most common form of family violence, occurring four to five times as frequently as spousal or parental child abuse, Caffaro said. According to some studies, nearly half of all children have been punched, kicked or bitten by a sibling, and roughly 15 percent have been repeatedly attacked. But even the most severe incidents are underreported because families are loath to acknowledge them, dismissing slaps and punches as horseplay and bullying as boys just being boys, he said.
The new research, conducted through interviews with children and their parents, measured the impact of a broad range of violence. It looked at physical assaults with and without weapons and the destruction or stealing of property, as well as threats, name-calling and other forms of psychological intimidation.
Overall, a third of the children in the study reported being victimized by a brother or sister in the previous year, and their scores were higher on measures of anxiety, depression and anger.
Caffaro said that the effects of sibling abuse often continue into adulthood. Over the years he has treated patients who struggled with emotional issues and sabotaged themselves in their careers because of repeated humiliation they experienced at the hands of a brother or sister.
“It can erode their sense of identity and their self-esteem,” he said.