How does the author use foreshadowing in Fallout?

Hunter was adopted by his maternal grandparents and given a fairly normal and secure upbringing. However, Hunter is haunted by the idea that his biological father raped his mother, resulting in his birth. This idea, this fear that he is somehow not a good person because of his father's actions, cause Hunter a great deal of emotional turmoil that is beginning to leak into his relationship with his girlfriend, Nikki. This foreshadows for the reader a time when Hunter might make a mistake that can cost him his relationship, if not his emotional sanity.