This is a very serious issue, and one that is challenging for those of us who have elderly parents. Until they become completely incompetent, and somebody institutionalizes them, our parents will always think of themselves as our parents, and as us as their kids. We aren't supposed to tell them anything; they are supposed to tell US stuff! When I tell my octogenarian Dad that he isn't the great driver that he used to be, he looks at me like I have 2 heads (and of course he wouldn't know if I did because he can't see that well anyhow or hear for that matter; probably doesn't even know that people are honking at him!). The idea, I believe, is to retain independence at all costs and to never, ever surrender to the kids!