Who is Uncle Jack Finch ?

He is of course Atticus's brother, a doctor Jem and Scout are very fond of. He is very much like Atticus. The children seem to confide in him when they don't want to worry their father. He does not have a wife or kids but seems to be a bridge between the adult and child world for Scout.

Oh, Uncle Jack punishes Scot over the Francis incident but realizes that he did not hear her side of the story before he jumped to conclusions. He is one of the few people who can acknowledge a mistake especially to a child.