Think sibling squabbles are a normal part of growing up?  A new study says they may do more harm than parents realize, affecting kids well after they have moved out on their own.

The study, conducted by researchers at the Universities of Oxford, Warwick and Bristol and University College London followed 7,000 children to document their experiences with sibling bullying and how it affected them later in life.  Researchers asked the children first at age 12 if they had experienced bullying by a sibling in the form of hitting, saying hurtful things, ignoring them, or lying to or about them.  Once these kids turned 18, they did a follow up evaluation on the participant's mental health.

The good news is that most of the children surveyed did not experience sibling bullying to the level asked by researchers.  But the 786 children who said they had been bullied by a sibling in childhood were twice as likely to experience depression and anxiety and have issues with self-harm than tthe other children.

Girls were slightly more likely to be victims of sibling bullying than boys, particularly in families with three or more children.  More often than not, older brothers were named as the siblings responsible for the bullying.  On average, bullied children felt that the bullying had started around the age of eight.

Researchers were clear to point out in their study that they weren't talking about the normal cases of teasing and rivalry that are common place among siblings.  Rather, they were focused on the incidents that involved verbal or physical violence that occurred several times a week.  And they are urging parents to take these incidents of bullying as seriously as they would if they occurred outside the home - particularly in a school setting.

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