Just off the cuff, I think there’s more to this issue.
I believe privacy laws vary from state to state, and in any case there may be defenses against these sorts of action. With libel, I know, if statements are accurate that is a legal defense.
Newspapers and TV news would be out of business if these sort of privacy claims were valid. Admittedly they have bigger legal funds than the average author.
Still, it would undermine the intent and credibility of memoirs if personal information of the kind you mention had to be changed in a radical way. I’m all for being sensitive to people’s feelings, and perhaps changing or omitting names in exceptional circumstances (having alerted the reader to that alteration). But for a father to delete references to children and grandchildren seems to go too far.
As I say, these are spontaneous thoughts, offered without benefit of research.