Im worried

Question
Hi Becky,
I am in a bit of a pickle at the moment, I recently moved in (roughly 2 months ago) to a friends with my boyfriend and our 2 cats!
The problem is our friend already has a cat which is quite aggressive and at first he would not accept either of our cats into his home but then everything was ok, they seemed to be tolerating each other...that was until about a month ago when we had a cat flap fitted.
Now our friends cat (Carwash) is being aggressive toward our girl cat (Pumpkin-about 2 years old) and I am very worried as she has scratch marks all over her back from him and she is hardly coming back home at all.
Carwash keeps garding the cat flap and whenever he sees Pumpkin he runs after her and hits her. She just keeps rolling onto her back and lying there very submissive but he still doesnt stop.
The only time that she comes in now is to have a little food (which she wolfs down at an alarming rate) and then shes back off outside.
Carwash is only a kitten (hes not even 1 yet) but he has been a very aggressive cat from the start and he often lets you stroke him and then he turns around and bites you or hits you.
I dont know if he is doing this to Pumpkin as a social status thing or if it is because he is not getting the attention the he desires from his owner. Also, I am not sure how receptive our friend will be to re-training his cat-he can be very difficult sometimes (the owner and not the cat...this time-LOl) I am really very worried that Pumpkin will not come back soon and that she will find another owner...we cannot afford to have her chipped at the moment.
The main problem that I am finding is that I can monitor them in the house but I do not know how to punish Carwash and as soon as they are outside I cannot watch them anymore and Carwash is being very aggressive again.
I do hope that all of this makes sense and that you are able to help me with this HUGE problem.
I really am getting very worried as they have been fighting again just...
Thanks so much
Joy

Answer
Hello Joy!

You didn't say, but are they all fixed?  Carwash is being very aggressive partly because he has not been neutered, and partly because he is defending his territory. It's extremely unfair for Pumpkin to be constantly beaten up and it sounds like she is having to fend for food too.  You need to make sure ALL of them are fixed or you're going to have kittens to deal with. This will help somewhat on Carwash's agressiveness.  They may eventually get along, but then again, they may not.  If you have no other choice and have to live there, then you may want to consider giving Pumpkin another home.  It's really unfair to her to have to live like this, in fact, it's almost cruel. I'm not trying to be mean, but for her sake, I would consider finding her a new home before she is severely traumatized and/or injured.

God Bless,
Becky
Becky