Something similar happened to an old friend of mine - he didn't know he had diabetes, and due to the resulting nerve damage in his feet had no idea anything was

Something similar happened to an old friend of mine - he didn't know he had diabetes, and due to the resulting nerve damage in his feet had no idea anything was wrong until after gangrene had set in. I haven't seen him in a while but I understand he came out of it pretty well, in that he "only" lost a few toes and managed to keep most of his foot. I hope your dad is managing ok and avoids this sort of mishap.