my son turned 4 in November. His sister is almost 1 1/2, and until she was born he was almost a perfect little angel. Now he shows some aggressive behavior, and recently has gotten way worse at listening, and will not talk to me about what is bothering him when he gets upset. When I ask, he just pouts or gets more upset. I try to show him attention as much as possible but obviously since his sister was born he doesn't get as much. I just am frusterated that he won't tell me what is bothering him so I can try to make things better. Why does he not understand I want to help him and talk to him. I want to fix this problem before it gets worse, any ideas?