This is JMHO based on personal experience/observation:

When we're little, we learn ourselves through our parents' eyes. We don't have the internal resources to function independently, so we have to look externally for that information. A parent/adult's job it to model and teach us to become independent, and part of that independence is self-reliance and the ability to trust in ourselves- so we don't have to look externally for validation. Unfortunately, many parents aren't up to that challenge, but some young people still find a suitable mentor in a teacher, other relative, etc. Some don't ever find anyone to teach them that. At the end of the day though, who wouldn't want that acceptance and approval of a parent? They are very important people in our lives, no matter how they function or don't.

My H was the opposite of Revenge Tour's sister, but it seems like maybe the internal regulation never got developed in either case. H could do nothing right in his parents' eyes. At 53, he's still trying, though I'm pretty certain he can't see that's what he's doing. And sadly, he's never going to get their approval- but it's one of his compulsions to keep on trying. So he keeps looking for the external validation of his parents, and even others around him, rather than being able to look to an internal part of himself that can tell him he's okay.

Anyway, that's my take on the aspects I've seen. Not sure if that might help.