Hi everyone, I'm new. I've been trying for a long time now to approach this in a way that works, but nothing has worked, and I'm in a bit of an awkward position. I'd really appreciate some insight. My step-son lives with me and my wife (his biological mother) every other week, and with his biological father the other weeks. I have been in his life since he was 1 year old, so a strange man magically coming into his life is not the issue. Step-son = 9 years old Daughter = 4 years old Generally, the weeks he spends with us are extremely taxing. Here's a quick rundown of what goes on: He is completely attached to his little sister, good and bad. Even when she doesn't want him messing with her, he doesn't listen. It's like he is incapable of sitting beside her without poking her or trying to egg her on. When they play together, they cannot seem to play calmly. It is always running all over the sofa and, naturally, someone usually gets hurt, we shout, he gets mad, etc. He doesn't listen to me or his mother. For example, I tell him no ball in the house, he keeps playing (kicking around like soccer). I have to literally take the ball, and then he laughs or something. Then he finds a balloon and starts doing the same thing. Complains about homework (though somewhat less the past few weeks, amazingly enough) Says "no" to nearly everything. I could say "the grass is green" and he would say "no." Talks back to me and his mother, rude Talks extremely childishly the majority of the time (cursing, slang, poop and pee, etc) Seems to have only two volume levels: Loud and Even Louder (his normal speaking is much louder than me, his mother and his sister) Talks generally negatively when it comes to things he isn't immediately interested in Everything is a competition Jealous Blames others for almost everything I don't know his father. From what I understand, he is extremely attached to his father and seems to view him as a best pal. Calling him at random times to ask about his score on an iPhone game, etc. I think he seems to get whatever he wants when he is living there (his father is single), whereas at our house he has to share the house with an additional 2 people. He also sleeps in the same room with his father and same bedtime as his father (late), while we have a bedtime at our house (which he fights tooth and nail). Compared to his friends, his movements are very explosive and hyperactive. His friend could be walking normally through the house, but he himself has to run and shout. I love him and the times when he is well-behaved are really wonderful. He can be extremely sweet and thoughtful, fun and funny. But the unfortunate thing is that his little sister seems to be a massive trigger for him. If it's just him, he is much more likely to be calm. But as soon as she is in the picture, it's like a hurricane enters the house. In general she is far more calm than he is. She doesn't HAVE to be playing with him, but he MUST be playing with her, if that makes sense. The only thing I can think of is to literally write out the rules, be strict, strict, strict and relentless in enforcement. I also feel like he has ADHD, but here it gets very complicated, because we couldn't take him to see anyone without his father's consent, and his father has already vehemently denied the idea. Apparently his father doesn't see the signs we do, he seems to do well and not misbehave in school, but when he's with us and his sister, all bets are off. Family vacations are exhausting and don't really even feel worth it. It is so frustrating. I don't want him to get into bad things later in life and I want him to be self-confident (which I think he lacks somewhat, possibly because of the split household). I don't know what to do. I try to be a good role model and tell him things I've learned about life and success, etc, but it's pretty clear that his father is his chosen role model. Any ideas or directions, methods, books, etc. would be greatly appreciated. Thank you.