Child abuse, like slavery and genocide, is one of mankind's great horrors, and therefore hard to turn into literature without going too far. The balance between honoring the reality of the victim's experience without becoming unbearable is delicate, especially when writing for children, but author Susan Shaw gets it right. It's real (except perhaps for some overly fortuitous timing at the end) and moving without being melodramatic or graphic.
Unlike many other novels of this type, the author doesn't shortchange the lasting psychological impact of Charlie's experiences, nor does she demonize the parents: What they did was terrible, but the mother is passive out of terror, and the father is genuinely ill and, in his warped way, doing what he thinks is best. Charlie's recovery, the main theme of the story, is also realistically slow -- the book has to skip over years at the end to get him to a place where he is even beginning to function normally. In all, it's a powerful and hopeful story.