Sibling Bullying May Lead to Depression, Self-Harm

Children who revealed they had been bullied by their brothers or sisters several times a week or more during early adolescence were twice as likely to report being clinically depressed as young adults, according to a new study.

They were also twice as likely to say they had hurt themselves within the previous year compared with those who had not been bullied.

The study, published in the journal Pediatrics, is the first to investigate possible links between sibling bullying and clinical depression and self-harm in young adults - a relationship that has, until now, been ignored by academics, policy makers and clinicians.

"Forms of bullying where victims are shoved around the playground or targeted at work have been well documented, however, this study uncovers a largely hidden form of bullying," lead author Dr. Lucy Bowes, from the University of Oxford, said in a statement. "Victims of sibling bullying are offered little escape as sibling relationships endure throughout development."

"We are not talking about the sort of teasing that often goes on within families," she added, "but incidents that occur several times a week, in which victims are ignored by their brothers or sisters, or are subjected to verbal or physical violence."

Bowes and her colleagues looked at 7,000 children aged 12, who answered questionnaires on their sibling relationships and later took part in a follow-up when they reached 18 years of age.

Of the 3,452 children who qualified for the study, 1,810 said they had not been bullied by a brother or sister. However, among this group, 6.4 percent had significant depression, 9.3 percent experienced anxiety and 7.6 percent had self-harmed in the previous year.

Of the 786 children who said they had been bullied by a sibling several times a week, clinical depression was reported by 12.3 percent, 14 percent had self-harmed in the previous year and 16 percent of them reported anxiety.

The link between being bullied by their siblings as a child and later mental health disorders was found to be similar for both boys and girls, and most of the time started around age eight.

"Even though we cannot be certain that this relationship is causal, we think it likely that interventions to reduce sibling bullying would improve the mental health in the longer term," noted co-author Glyn Lewis.