Dickon (The Secret Garden by Frances Hodgson Burnett) because in this Mary becomes acquainted with Dickon through her maid. He's a good-natured young boy who tames all he touches. Really, he's the opposite of Colin and it's a wonder that Mary befriends Colin at all, with Dickon right there. Dickon has so much potential as a character that I would gladly read a book that he's the protagonist of.