sibling cat rivalary

Question
We have two surmese sisters from the same litter, one brown and one beige, they are two years old. The brown, we got first and 3 weeks later the beige. The brown is a lot smaller but has always been the dominant one. They have been inseparable sleeping ying and yang and playing together. Suddenly they have started fighting and the brown one spits. At times in the night they will still curl up together but mostly they keep well away.  When they do get together there is excessive grooming that you know will end in tears. Just before this all happened the brown one had a bad incident whereby she jumped and bit on a "glow stick" when the lights went out and had the filling in her mouth. The beige one went to lick her and it was as if she thought the other one had done it. Is ther anything we can do to retrain them?

Answer
Hi Margaret,

Sorry this took so long to answer. I have a a very sick cat here that took me away from the computer. Glow sticks have hydrogen peroxide in them. The taste of the stuff probably startled them but I don't think that is the cause of your problem. I think it might be redirected aggression. Take a look around and see if there is a cat or dog around that they can see, (maybe out a window or door). I think this is what is setting them off. After you find the area, (animal), that is bothering them, remove their line of sight of the strange animal.

Next try a cat intro protocol with them. This will be the best thing to get them together. But first make sure they can't see the strange animal. Here are a couple of links that might help you. Good luck.

http://www.kingstownecatclinic.com/Redirected%20Aggression.htm

http://www.catcenter.org/Documents/11_cat_to_cat_relationships/pdf%201102%20sfsp...

Ciao, Karen