Yeah, 20 years is a long time for a kitty. I'm fighting with one of mine right now, and he isn't all that old (2007). He passes a stone a couple of weeks ago, I had him on amoxycillin. Now, he's got some kind of respiratory thing going on. I've been spoon feeding him and giving him water with a syringe. He's looking better this morning, even purred a little. I just don't know whether I am prolonging the inevitable (it's all inevitable, isn't it?) or helping him come through a bad spell.