My nephew has high functioning autism and ADHD. He struggles to understand social cues and since about year four has be bullied relentlessly by boys who were once his friends. He’s now just gone into year 7 and these boys are still at it. Last night my nephew said he doesn’t want to live anymore 
My sister and BIL have tried approaching the school and they have done nothing about it. I’ve told her she should just pull him out but obviously it’s not my place as he’s not my child. My sister isn’t the most hands on mum so doesn’t seem too affected by it, BIL has been really on the case though (they’re separated). It honestly breaks my heart, he’s the sweetest kid and wouldn’t hurt a fly.
What can we do?