My mom and my 12 year old brother are currently living with myself, my husband, and my five moth old. I have always suspected something was not quite right about my brother, and I am now worried about him possibly harming my son. This is going to be long, but I need some advice. Some background on my brother: His bio father had bipolar depression and psychosis (he would hear voices that eventually led to 3 suicide attempts). My brother's first years of life were filled with instability since his dad was at the worst of his depression and became emotionally abusive of my mom and my other brother (not me, for some reason). My mom and him eventually divorced, and it was not amicable in the least. When he moved out and got his own apartment, he would frequently have pornographic magazines laying around the place, and my brother (3 at the time) was caught multiple times hiding under the office desk looking through them when my mom would go pick him up. He would also rub his toys on his penis when he would take a bath. This behavior was disturbing at the time, but chalked up to boyish curiosity, ad my mom repeatedly asked his dad to stop leaving that content within reach. He also started to get joy out of grabbing the fish out of the fish tank and squishing them in his hands. We stopped buying fish. We also started noticing he was prone to lying. About aything! He would make up stories on the spot. Once again chalked up to him being so young. Fast forward to school years. He has had problems in school since day 1. From normal tantrums to outright fits of rage. My mom would get calls everyday about his behavior. He would also poop himself at least once a day until the age of 9. He has never had any friends because he would always end up in a fight. Around 3rd grade he started getting bullied everyday at school, and so his behavior and tantrums got worse. His dad expressed concern about his behavior and got him to a psychologist who said my brother had some form of detachment from reality and the consequences of his actions. He said that he seemed to show signs of depression but could not be diagnosed until he was older. The lying only got worse as he grew up and so did his sexual curiosity. I often caught him trying to sneak into the bathroom when I was showering, so we bought a bathroom door that locked. I moved out when he was 8. He started to hate spending time with his dad. One day my mom came home to find he house in disarray, he was 9 at the time and had been dropped off by his dad. My brother told my mom that my stepdad had broken in and wrecked everything exclaiming he would kill his mom one day. His dad always said that was not true, but at the time my mom believed my brother and got a restraining order on his dad. Around the age of 10 my brother started telling my mom he sometimes thought of hurting himself, and that he was sad most of the time. My mom remarried, which brought about a world of problems with my brother's dad. As his depression worsened and so did his psychosis he would lash out at my mom and my brother through verbal insults quite often. Last year (my brother was 11), my brother's dad died. Sudden cardiac arrest out of nowhere (more or less, he had an enlarged heart and his liver was failing from his drinking). When my mom told my brother his reply was "Oh", and he went about his life as usual. No show of emotion or grief. He was more concerned about getting back to his video game (video games and tv is all he ever does). That was concerning. Current Events: Around this time my mom and her husband went through financial struggle as they were both laid off. I told them to come live with us. My mom has always worked full time, and my brother used to spend a lot of time alone, which is why some of the things that we started to notice weren't noticed until there was someone constantly home with him, or maybe he was getting worse. It was small things, like the dogs would wimper whenever he was around. I later found him on the side of the house digging the handle of a shovel into the dog's paw while he held him down. I forbade him from being around the dogs. My husband walked into the bathroom one night to find a strange wad on the toilet seat. It was ejaculate. He had masturbated unto the toilet seat and left it there. He found this three more times after having told him to never do it again. I had give him a tablet for his birthday and my mom decided to take a look at his search history and apps. He would watch nothing but porn on it. Weird porn. One of the videos featured an asian female being fisted by three men. And that was the mild one. He was also talking to multiple girls on the kik app. HE would ask them for nudes and was "sexting" many of them. One of the girl's fathers went on there and told him he would report him to the cops if he ever messaged his daughter again. Ok, well maybe he's just being a boy. I don't know, but it was concerning. I caught him hurting the dogs a few more times after I had told him to not be around them. I had a baby, and from the start did not feel comfortable leaving him alone with my brother. He continues having trouble in school and even failed sixth grade. His teachers state that he still has angry outburst whenever he is asked to do his work. He will bang his desk or run out of the classroom. He mad a friend in the neighborhood, a week later the boy's dad came to our house and asked that my brother never come over again. He had told the boy' younger brother that he had "something sticky and hard in his pants. Do you want to see?". My brother claims he never said that. I walked into the living room one day, when my son was in his swing and saw him sitting in front of him with his hand hovering above my son's head, not quite touching him and looking concentrated. I made a noise and he startled and jumped back. I don't know what to make of that and maybe I'm looking too much into it. He has frequent nosebleeds and constantly leaves blood in the bathroom. Going into the bathroom you never know what you're going to find, blood, semen, poop (he seems to always smear it on something). He loves scary movies, violent movies, and violent video games. He got in a fight at school and broke a boy's leg by stomping on it. He breaks things around the house, my mom's perfume bottle, dishes, and claimed they were accidents. We found a lighter covered in lighter fluid in the back porch, maybe it wasn't him, but it was suspicious. He got on my mom's phone and used her google account to download a game, then spent 500 dollars on add ons(he knows her google password and she had her card saved on there) . Google was kind enough to refund the money. His tablet was taken away, but he would go on the living room desktop to watch porn. The weird porn, again. He always apologizes afterwards. I'm sorry is his favorite word. When he wants something out of mom he hugs her and kisses her and then asks, but disrespects her all other times. He lost his room privileges after the 500 dollars. We moved his bed to the living room and told him he had to complete 60 hours of chores to earn his room back. He was angry about this, and especially at my husband since it had been his idea. After catching him watching porn on the desktop again my husband reprimanded my brother. The next day my husband had bought a soda, drank half of it and left it on his computer desk. Later that day he went to drink from his soda, took a swig and thought it tasted weird so he spit it out. He was shocked by the smell so he ran to our room and asked me to smell it. It was pee. He threw up and washed his mouth before going to find him. He asked him if he had peed in the can and my brother said he had done so because both bathrooms were taken and he really had to pee. My husband asked why he had put it on his desk and my brother replied that he had set it down to throw out late but had forgotten about it. The only thing is that everyone but me had been at work, so the bathroom in my parent's room was vacant the whole day. He said "sorry bro" and went to bed (it was 12am). I don't know what to make of this. I'm concerned that he's going to get worse. Or maybe there's nothing to worry about and he's just a kid? I don't know but I just have this feeling that he's not ok, and that I shouldn't leave him alone with the baby.