re: son has humerus surgery - how to advise my wife?

Is this his first major surgery or broken whatever? Because, IME, the hardest part is not knowing HOW long you are going to be in pain if it a first time thing. He'll start feeling better quickly and your wife will be off the hook.

Another thing - Please don't think me callous for saying this - is that if he, at any point in his life, had a problem with prescription pain pills (maybe something you didn't know about) - Having somebody else there would "keep him on the right path" during recovery. Just throwing that out there as a small chance scenario.