*sigh* new problems with adoptee

This cat must be bipolar or something. One day shes sweet and well behaved..the next day shes dumped out every trash can, knocked down my snake cage, knocked over every ornament and is hissing, and swatting at me when I get near her.

I've put up with it for the past week but tonight shes actually gotten fairly violent when I go to pet her. Theres no reason for her to act like this, nothing has changed since I got her.

The cats have been together for 4 weeks now and they seemed to be getting along but lately, Mya will randomly chase Avalon off into a corner and beat up on her. =(

Any ideas? =/

Is she truly violent or is she just really hyper? Sometimes kittens can do a lot of damage when wound up and never even realize they hurt anyone. I'm not sure how old your kitty is but if my hunch is right then it's consistent with her other behavior i.e. knocking things down. If so then take heart! They don't stay kittens forever, both a blessing and a curse.

I wouldn't take it as kitten playing. I've seen and played with rough kittens. She hisses bites, and swats at me when I pet her. Granted its very rare that she does it and she only recently started doing it. With the trash cans I'm just going to have to get ones with locking lids or something.

Did you slowly introduce the two cats?

Cat relationships are tricky and hissing is perfectly normal. They are establishing the new hierarchy of the home. It's a stressful time for the cats. I know it's been a month, but that's not a long time at all when it comes to cat introductions. The split personality thing could just be the cat adjusting to a new situation and new environment.

To ease the tension among them, you can try something like Rescue Remedy (Whole Foods and other natural stores like that would have it, it's made for people but can be used for pets).