Leslie, I'm so sorry to hear about Graham's pain. And yours. It does make it harder and more obvious now that Kersey is a part of your family, I'm sure. Some of the other suggestions people have made sound great, especially the swimming.

I'm so tempted to say" Oh everything will be fine, don't worry" but that would be something a non-Pet Talker would say who doesn't understand the pain and hurt you feel over your precious Graham and his quality of life.
And I do and I'm sorry and wish there was more that I could do for you.