Someone help me!! I have a 3 month old part siamese kitten. He is cute and full of personality. Purrs all the time. He is beating up my 5 year old, very quiet, fat cat. She has marks on her ears from him. He attacks her and she hisses and then lets him bite her. I don't know what to do. He is trying to dominate her I guess. They have different food but share a cat litter. I thought the older cat is usually more aggressive to the younger one. We are opposite. We have two dogs that he plays with all the time. Whenever he wants to play he always has playmates so he isn't bored. He gets most of the attention so he shouldn't be jealous. My older cat is very quiet and mellow and just hangs out. She isn't very social. She is looking so sad. Does anyone know what I should do????????