Throughout the story of "Lost Boy" David Pelzer, the main character, serves as a representation of many different aspects of the things severely abused children go through. Throughout the story, he must learn to deal with many different things, from being outcast due to not being the same way as others, to dealing with his belief about himself, which is that he's inherently "bad." There is a part of him that tells him the abuse he went through is his own fault. Due to the trauma he faced, he also struggled to feel as though he was truly safe, often believing his mother would find him.

Ms. Gold is the social worker for David's case. She helps David get adjusted into foster care and being away from his mother. She helps him through legal processes and gets him into therapy. She is a very kind and caring woman, often referred to as David's "angel". Ms. Gold listens to him, provides for him, and comforts him when he is struggling. She gets him into different foster homes and helps him adjust to new places. She's a positive character who supports and understands David as he goes through struggles such as healing from abuse, coping with grief and guilt, and struggling to fit in or see his own worth as a person.

Catherine Pelzer, David's mother, is the cold antagonist of the story. Throughout David's childhood, she severely abused and manipulated him, which resulted in a lot of the issues David faces throughout the story. Her character is described as having a severe alcohol addition, which contributes to her severely abusive behavior. She is often seen acting cold and condescending, only referring to David as "The Boy," or "It." Her attempts to break David's spirit serve as the primary factor in David developing a sense of perserverance.

David's foster mother, Lilian Catanze, provided a safe healing home atmosphere and life for David. She has shown him kindness, respect, and independence throughout his time with her and she understands that he's having a difficult time coping with his trauma. Lilian treats David with respect and patience. She comforts him when he's upset or acting out and tries to help him manage that rage in healthy safe ways. She is a stable support system and has helped him get comfortable with adults and having a stable environment. Lilian has a positive effect on David by making him feel loved and valued which starts replacing the trauma his mother previously inflicted on his mental and physical state.