C.M.
I think you are on the right track with giving him the gift of your time. It would be totally awesome if all 3 of you could be there together. I am sure that would mean more than any gift. I know this must be a difficult time for your family. You didn't say but is he receiving hospice care? If so Hospice can help with ideas as well. I have prayed for your strength and peace for your father.
C.