One more thing I forgot.
Yes, the onus IS on the bad parent, heart. But that means absolutely zilch as far as the child's life goes after he reaches adulthood. The parent may refuse to take the onus. The parent may be punished for what he did. The parent may take responsibility for what they have done. Any number of scenarios.
Won't change a thing for the damaged child. Not a thing.
A wounded kid has to figure this out - that his success/failure is no longer connected to mom and dad.
Personal freedom/personal responsibility.