I will find you / Harlan Coben.

An innocent father serving life for the murder of his own son receives evidence that his child may still be alive, and must break out of prison to find out the truth.

Five years ago David and Cheryl Burroughs' son Matthew was murdered in his bed while David was asleep just down the hall. David is serving a life sentence in a maximum-security prison for the brutal murder; Cheryl is remarried. Then Cheryl's sister, Rachel, visits David-- with a photograph that a friend took on vacation at a theme park. There's a boy in the background who has a familiar, distinctive birthmark. It's Matthew, and he's still alive. David plans a harrowing escape from prison, determined to do what seems impossible: save his son, clear his own name, and discover the real story of what happened that devastating night. -- adapted from jacket