We lost our 19-yr old last October and our 21-yr old this past April. I think when they reach a certain age there is only so much that can be done for them. It's very difficult to let go, but there is a quality of life to consider. Our 21-yr old could not walk any more, so was lying in urine. She was fine otherwise, but how does one help an old cat who can't walk? She was very arthritic and was probably in a lot of pain. We tried medication, but....