Hi, new to the cat forum. Sorry to bore you all again with yet another weeing problem but I really need some help please. I have a 17 year old neutered tom who has a cat flap and had never tiddled indoors until recently. A few weeks ago I saw him spraying in the hallway and then found tiddle patches in the bathroom. I put a litter tray in there and thought he was using it ok but yesterday I caught him squatting to wee on one of the dogs beds. The vet has done two lots of blood and urine tests and says there is no health problem. I have been using Urine Off and have just ordered one of the black lights. What can I do, please help?