Hi! We adopted a 1 yr old cat that had lived in squaller conditions and almost died from giardia. We were told she lived with 5 other cats. We did a slow introduction to our 2 other cats, 5yr old female and 12yr old male. She went right after my 12yr old cat and he ran and it turned into a fight. Now we cannot let her out of my den where we put a door and some wire fencing unless we put the other two in my bedroom. She has got out and goes right after him. He is not a fighter but very sweet. She charges the gate if my 12yr old male walk by. We have tried so many things but nothing has worked. She doesn't bother the other female since that girl takes no nonsense from her. Should I give up? She is totally in love with me and cries for me. She can see us from the den but wants to be where I am.