We own five adult cats who have recently all picked up very strange behavior, very off from the way they normally act. I'm wondering if they are sick or simply coping with something else, either way something is very wrong. Their sleeping habits have changed dramatically, normally they will alternate their choice spots to slumber all over the house but suddenly they are either hiding in the basement or sleeping in their litter boxes. They come out to eat and run right back. They've begun to act erratic, mewing and climing to strange places they've never had interest in before. I've found small rashes on each one of them, a small spot of tiny bumps where they had been bitten by fleas, but they've long since started treatment for it and the odd behavior began a while before. Does anybody know why they might be acting this way?