* Percy's relationship with his father: Percy's relationship with his father, Poseidon, is fraught with complexity. He yearns for a father figure, but his father is a god who cannot be present in his life. Percy grapples with feelings of abandonment and inadequacy, wondering why his father chooses to be absent. This struggle is further complicated by the fact that his father is the one who unknowingly sets Percy on the path of danger and adventure.
* Percy's relationship with his mother: Percy's relationship with his mother, Sally, is a powerful contrast to his relationship with his father. Sally is a loving and protective parent who is always there for Percy. She tries to shield him from the dangerous world of the gods, but she also understands and accepts his true nature. Sally's unwavering support and love are crucial to Percy's journey and help him overcome his struggles.
* Luke's relationship with his father: Luke, the antagonist of the story, also grapples with a challenging relationship with his father. He feels betrayed and abandoned by his father, Hermes, and this fuels his anger and resentment. Luke seeks revenge against the gods, blaming them for the hardships he has experienced.
Overall, the novel explores how parent-child relationships can be both a source of strength and a cause of conflict. It shows how the absence of a parent, the fear of losing a parent, and the longing for a parent's acceptance can all shape a child's life.