Whose sibling is that?

Yes. It seems like you got those because you actually knew them. Ideally this game is supposed to make you figure them out solely by the resemblance. But that might be too hard, and such candidates are also very hard to find too.
 
He's the brother of the guy I meant to put in Name that former Celebrity. I put his famous brother there now.
 
Brooke Shields is not correct. But it looks like it could have been.

Who's his famous sister? (I think I should give gender hints)
 
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