Children who were bullied by their brother or sister in their early teens are twice as likely to be depressed and have self-harmed as young adults.
The findings come from a study published in the journal Pediatrics, which followed almost 7,000 children from the age of 12 until around 18 (Bowes et al., 2014).
Dr Lucy Bowes, the study’s lead author, explained that…
“…this study uncovers a largely hidden form of bullying.
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, 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.”
The children in the study were followed for around 8 years, during which their mental health was tracked.
Around half said they had not been bullied — of these 6.4% were depressed, 9.3% experienced anxiety and 7.6% had self-harmed in the previous year.
In comparison, of those who had been bullied 12.3% were depressed, 16% reported anxiety and 14% had self-harmed in the previous year.
The link between bullying and self-harm was the same for both boys and girls.
Professor Dieter Wolke, one of the study’s authors, said:
“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.
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 study found that older brothers were often the perpetrators of bullying and girls were more likely to be the victims.
Sibling bullying started, on average, at the age of 8 and was more likely in families with three or more children.
Professor Glyn Lewis, another of the study’s authors, said:
“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.”
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Image credit: David Goehring