I have three cats and they've all started acting strange. The two that stay inside attack each other all the time ; and I mean attack, it's violent and they actually hurt each other. My third cat likes to hunt and is getting rather skittish around the house, bolting if a door opens too loudly or something. She also normally comes in before I'm going to bed by finding a room with lights on and tapping the window if no windows are open. But now she pads manically at the window, making the meow as if I'd stepped on her tail and sometimes even jumping at the closed window. Tonight, she smacked into my door and made a scream at if she was being killed before flailing around a bit and bolting before I could unlock my door. I managed to get the door open just in time to see her catapult herself into a Holly bush. I've had these cats for four years with no issue. They're docile and well trained but - what the heck is happening? Are the cat fights and late night manic episodes related?