I would never judge anyone by their family as obviously nobody chooses them.
However, I do admit that I do judge people by their friends. For example, I've never understood why bullies and bitchy people have the large number of friends that they do. There's a woman I work with who's just horrible to anyone subordinate to her. Despite this, she has more friends and fans than anyone I know, but if I know that someone's friends with her, I tend to avoid them. Quite simply, I don't want bullies or their enablers in my life.