I studied Genie in college. Based on the true story of Genie (Katie, in the movie) who was kept strapped to a potty-chair and locked inside a cage by her father. I learned about her in Psychology class and developed an interest in Feral Children.
Dear Daughter by Elizabeth Little. After being released from prison on a technicality, Janie Jenkins tracks down the one lead she has on her mother's real killer and is startled by what she uncovers about her mother's past in a small South Dakota town.