Andrew Vachss

All children are born pure egoists. They perceive their needs to the exclusion of all others. Only through socialization do they learn that some forms of gratification must be deferred and others denied.

Many of Judy Blume's books - which I devoured when I was growing up and where I found characters that were believable because they were a lot like me - caused considerable consternation when they were first published, but now they're widely accepted as an essential part of the children's literary canon.