What is a short summary of The Lost Boy?

The Lost Boy is a memoir in which the author, David Pelzer, tells the story of his adolescence in the foster care system. It takes place after Pelzer’s first book, A Child Called “It,” which describes the horrible abuse and neglect his mother put him through. In The Lost Boy, David’s teacher contacts police with suspicions of abuse. He is then removed from his mother’s care and is placed in a transitional foster care home. David is still scared his mother will come find him and abuse him, and he’s worried about telling authorities “the family secret.”
During his hearing, the court rules to permanently remove David from his mother’s care, so he is moved to different foster homes as he struggles emotionally from the years of abuse. The emotional implications of the abuse lead him to stealing and getting into trouble. When he is falsely accused of starting a fire, he is sentenced to a juvenile detention facility, but he’s only there for 100 days, due to his good behavior.
Throughout his experiences during adolescence, David develops a strong work ethic, and he eventually joins the United States Air Force. His life then turns around as he finds the home he’s always wanted with his wife and son.

The Lost Boy is a true story about a child who was placed in the foster care system at the young age of twelve, after being relentlessly abused and tortured by his mother and neglected by his father. 
The story shows David undergoing a variety of physical and emotional abuse by his mother. After he is kicked out of the home, David has the opportunity to alert the police of his continuous abuse but does not. Eventually, his teachers take action, and David is placed in the foster care system.
Much of David's time within the system is spent in great fear. He worries that his mother will come and take him away to subject him to more abuse. On the other hand, although he despised the torture he endured living at home, David still yearns for love from his mother. 
David is eventually released on his own, and from then on, he works through many difficulties (juvenile detention, education, etc.) in order to find the happy life he has always dreamed of.