Philip, I'm so very sorry for your loss of Tux. You know I just suffered my own loss of my cat Cinders, so I have a good idea what you're feeling. Feline Leukemia is a bad bad illness. I'm so sorry. As I always tell myself and others when this sort of thing happens, it's not the death you would wish for them, but it's the best death you can give them. (I always pray they'll just fall asleep one night and not wake up and that's how I'll find them, curled up safe in their beds. So far, in 29 years, only ONCE.) Best wishes, Annie