Help!! My older cat might have thyroid cancer and my new Egyptian mau keeps attacking her

[Qidoctor]

Hi Karen, thanks for the ideas...I did pick up a leash for him and have started introducing him to it in the house. He's not thrilled, but I'll keep on it and eventually we'll get outside. I'll pick up some new toys too. Do you think his behavior will subside once he's more acclimated and gets more exercise? Thanks again.

[Karen]

I do think his behavior will subside once he is not only better acclimated, but getting plenty of exercise! I'd take him out on the leash as soon as possible, as most cats will begin to associate "harness means I get to go OUTSIDE" pretty quickly, and unlike a certain bunny of mine*, will be too concerned with exploring things to be bothered fussing with the harness and leash.

*Miss Hoppy, now at the Rainbow Bridge, was so bothered by the fact that the harness mussed her fur that she turned into a fur-covered brick. Yes, if I pulled hard enough she'd move, but would NOT hop on her own. We gave the harnesses to a shelter, and took to fencing in an area outside for her to play in, only while supervised!

[Annie89121]

It sounds like your younger kitty needs another youngster to play with so he will leave your senior kitty alone.

I have the same problem with my Frankie. When I first got him and he started being rough with my 2 senior kitties, I used a squirt bottle to squirt a little water on him when he got rough with any of them.
Now all I have to do is grab the squirt bottle and he knows to stop what he is doing.