14 year old brother stole my underwear

hi everyone I'm 17 and I have 9 siblings. I have a lot of stuff going on and I just thought this is the place to get it off my chest. my little brother is 14 and has a girl twin and we have had a lot of problems with my brother. he is at a kids camp right now and has been there for two months because it's part of his probation. but here's the thing he has stolen from stores, family members and people my dad works with and he's looked up rotten porn (not against porn but I'm against 14 year olds looking at thing girls down) and before he left for camp he had stolen a pair of my dirty underwear and I was like ok that's weird but after getting caught he'll never do it again right?? well I came home yesterday and my mom found NINE PAIRS of my Victoria Secret thongs and a couple pair of my Target underwear. and he jizzed all over them. also before he left for camp he knocked on my door at 2 am and asked to see my tits so he could sleep better and I said fuck no and then i tried closing my door and he FOUGHT AGAINST MY WEAK ASS 5 foot girl muscles to FORCE my door to stay open. and then I shoved him and closed it. his twin sister is terrified of him. has anyone had a similar experience or have any advice for me? my mom is struggling too and doesn't know what to do 
ps I'm not a troll. THIS REALLY HAPPENED and I'm on annonomous because it's embarrassing