Ok so when I was around 8 my older brother was super mentally unstable. He attempted to kill himself multiple times bc if his gf and did extreme self harm ( to the fat layer or even bones ) 
He used to show me loads of horror games like fnaf and stuff bc he liked being mean to me. I forgave him a lot though lol
He became drug addicted and almost went to an inpatient clinic. He stabbed my dad with the glass from his broken phone. 
I have now discovered he was suffering from psychosis during this time ( induced by drugs ) and was suspected of having bpd. He is fine now and we have a healthy relationship. We are very close. My mum told me most of this info. I do not rememberer most of  it even thiugh it was only a few yrs ago.