The sun brings me comfort

The 12 year old knew his life wasn't normal. He knew but there was nothing he could do to change it since he feared everything would be just like his father said.

But maybe there was more to life than the tiny room he lived in.

Or:
A boy who lived his entire life in a small room under the house and learned more about the world outside when he was 12 meeting the people who would change his life completely.