sudden aggressive behavior

[Biz52403]

I have two cats - 10 and 8 years old.  Within the last 2 weeks the 8 year old has taken to suddenly attacking the 10 year old.  This is extremely od behavior...the younger has always been a very social and extremely affectionate cat...to myself, my wife, and the his older brother.  It has gotten to the point where the older cat is scared and will not go near his brother...

This is a very sudden and extreme behavior change...any ideas or suggestions?

[LynneAV]

If everything checks out health-wise, there is also the phenonomen of displaced aggression. For example, at our house, Annie would frequently attack her sister Lizzie whenever a roaming outdoor cat would trespass on the property. Annie couldn't get outside to get at the intruder, so she took her frustration out on poor Lizzie.

[zodiacqueen]

Hi, sometimes behavior changes can be related to a health condition.  I would take him to the vet and get some blood work done.  Have you noticed any other changes in your cat-eating habits?  Litter habits?  Sometimes thyroid conditions will cause behavior problems, too.

I think it's worth checking out, and your poor 10 yr old needs some peace.  I wish you the best of luck and please come back and let me know how the eating and litter habits are!

ZQ