Hi! We have 2 cats and my 14 year old cat has been acting funny. We had all the test done on him to make sure he is not sick. Now he howls all the time, he doesn't want to be touched and he is missing the litter box when he poops. He has also started to attack the other cat for no reason. How do I help him. He is loosing a lot of weight too and like I said the doctor has no clue whats wrong with him. I'm thinking of getting a second opinion. I'm really concerned, he's even started to bite me. Oh, he also has really good days and he'll come and sit next to me and purr. What should I do?