Older cat/new kitten behavior problems

My first cat THOMAS is 1 1/2 yrs old. He was the ONLY cat for 1 1/23 yrs.

I recently got a kitten 6 months old. Thomas now beats her up by biting her
abdomen, she screams and I run in yelling at THomas and then put him by himself in the bedroom for a couple of hours. Then he comes out and repeats the same behavior. I am going crazy. I don't know what to do to stop this
behavior. PLEASE HELP ME!!!!!!!!!!!!!!!!


Answer from Kate
HI
First of all are you sure he is attacking her and hurting her? I say this because when cats play it can look rather nasty. Is he growling or hissing when he does it? If not then it could be just play.

Also is the female cat spayed/ Is Thomas neutered? If not then having them both done will reduce any aggressive behavior. At 6 months old the female cat could be coming into her first heat if she is not spayed yet.

The last thing i can suggest is that if you do think that this is aggressive behavior the only thing you can try is to reintroduce the two cats again to each other using the safe method described on this page, it takes a little time and effort but can help to solve a lot of issues.

http://www.our-happy-cat.com/introducing-cats.html

best wishes Kate