Sibling bullying can greatly affect the mental health of children, according to new research.
Researchers from the University of Oxford found that those bullied by their siblings are twice as likely to report being depressed and to say they had self-harmed within the previous year compared with those who were not bullied.
"Victims of sibling bullying are offered little escape as sibling relationships endure throughout development," Lucy Bowes, lead author of the study, said in a press statement. "We are not talking about the sort of teasing that often goes on within families, 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."
According to the National Institute of Mental Health, girls are more vulnerable to depression than boys. The National Comorbidity Survey: Adolescent Supplement states that almost 11 percent of the adolescents in the United States have a depressive disorder by age 18.
For the currents study, researchers examined the data gathered from at least 7,000 children of mothers registered for the Avon Longitudinal Study of Parents and Children in the 1990s. Researchers told the participants to answer questions in 2003 and 2004 related to their experiences of any form of sibling bullying and if so, how often it happened.
The same children were followed up at the age of 18 years and their mental health was examined using an online questionnaire, known as the Clinical Interview Schedule. The teenagers attended a clinic to fill up the questionnaire. They were asked about their feelings and any recent self-harming behavior.
Of the 3,452 children tested, 1,810 said they were not bullied by their siblings. Researchers noted that 6.4 percent had depression scores in the clinically significant range, 9.3 percent experienced anxiety and 7.6 percent had self-harmed in the previous year. The findings also showed that of the 786 children who reported being bullied by siblings 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.
Researchers found same association of being bullied by their siblings as a child and later mental health disorders in girls and boys.
"Social learning and how to behave with peers starts at home, and when siblings are bullied it can have serious long-term consequences as we found in our study," Dieter Wolke, co-author of the study, said. "It is important that parents set clear rules about what is allowed in conflicts and they should intervene consistently when their children maltreat each other repeatedly."
The findings were published in the journal Pediatrics.
