A Child Called "It"

My independent reading book is called "A Child Called It", and I really liked this book because it talks about a little boy's struggle into escaping abuse from his mother. I know its really sad, and that's the bad part, but to see him be so motivated and have so much hope that he will escape from her really makes me want to finish this book. In fact, I finished the WHOLE book in 1 day; I stayed up till 2:00am :) The bad parts are when she repeatedly hits him, but treats his brothers like angels and feeds them delicious food, and I wonder.. why not him? What did he do to deserve this? This is a very sad book, but it's also very good.