re-introduction problem after short time

Question
We have to Bengal cats, male and female, brother and sister, been together since their eyes opened.  Both are completely indoor cats and normally run, play, and sometimes snuggle together when they are curled up sleeping.  Had to take the female to the vet for a little eye infection.  When we returned home about 2 hours later the male attacked her, and is still on constant guard.  He is even being quirky with us.  It's as if she is a total stranger invading his space.  Are their memories that short ??  Thanx much for any answer or advice.

Answer
Hello,

You did'nt mention how long this has been going on for since the vet visit? The thing is Bruce and Jeannine, cats do not have 'memory' like we we do, for example, we can sit somewhere and 'remember' and 'visualise' what we had for breakfast and who was there. Cats on the otherhand cannot think and visualise the past at will, as we do. Instead cats rely heavily on 'triggers' such as scents, the feel of something (material etc) and the look of something to trigger a memory and subsequent 'feeling' or reaction towards that particular stimulus.

One of a cats main communication 'tools' is scent (pheromones), and when you brought his sister home, he may have visually recognised her, but more importantly she would have had a different scent, probably an array of other scents that she had picked up from the surgery. This would immediately not have only confused him, but he would have found it threatening, and this is why he is displaying this behaviour. When you say that he is being 'quirky' with you, I'm not really sure how to answer that as quirky can mean alot of different things! But what I would suggest is not to try and force them together, for example, do not attempt to pick him up and carry him to her, also try not to break up fights unless real fur is flying! and definately do not use any form of punishment towards him if he is being aggressive , as this will probably cause him to become threatened, wary and aggressive towards you.

At feeding time, feed them at the same time but at a distance, so that they can see eachother but not necessarily get to eachother. For example on each side of a glass door (but not too close), and as they begin to show no aggressive behaviour, then simply over time just move them closer and closer removing any partition between them (this is best done at times they are doing something they really enjoy, like eating!).
Make sure they have their own 'safe area', that each one can retreat to if they wish to be alone or want to hide, as this will help to make them less stressed.
Both play with a seperate cat in the same room but at different ends of the room, give them food treats when they are not being aggressive and getting closer to eachother, if one gets aggressive then simply stop playing and re-direct him into another room.

What you want to be doing is slowly re-introducing them to one another, you do this by slowly over time moving them, by playing or feeding, closer and closer to eachother, positively reinforcing the 'good' behaviour you want with treats or whatever you find is your cats most favourite thing.  

I would also suggest installing a pheromone diffuser such as a Feliway, these can be purchased at pet shops and veterinary surgeries.

I hope this has helped you a little

Thank you

Kelly