So we have 4 cats, one of them, the eldest has started to need a litter tray at night, but one of our other cats pee's in all the trays in turn manning that the cat who needs it won't use any of them. Its becoming a real problem as he is peeing in our bedroom at night - not in the same place, all over!
I'm at the end of my tether, is there any reason why this would be cruel - to lock the elderly cat in our front room at night with his own freshly cleaned litter tray, obviously he'd have multiple beds, sofa, water food etc and its a large room, but he's not used to being locked in there and it would take him a while to get used to it, but its the only way I can think of to get him to use the tray.