well we dont know the whole story, what if the kidney of the adult son was damaged because of excessive drinking habit? and she had reminded him and scolded him over the years and he does not listen? im sure she has her reasons. plus, who’d want an older kidney? or to take your mother’s kidney, even if there was a match i wouldnt take my mom’s kidney, she needs it more than i. the older the person, the more wear and tear on the body and it’ll be hard for her to live.