"you can forget about any chance of a healthy adult familial relationship between them."
Such is life. Not everyone has a family to begin with.
You called it "normal and expected". When not everyone has it happen to them, that's not "normal and expected". (It's not necessarily abnormal, but "expected" at the very least is a stretch).
You called it "normal and expected". When not everyone has it happen to them, that's not "normal and expected". (It's not necessarily abnormal, but "expected" at the very least is a stretch).