When Ellie and Jay were younger, they tried to convince people they were twins. What does this detail suggest about the nature of their friendship?

Ellie’s mother begs her not to “go vigilante” when investigating Trevor’s death. Why would Ellie’s mother be worried?

The symbol of the leech appears throughout the novel, particularly adjacent to Dr. Allerton and Willowbee. What does the leech represent? What emotions are connoted through this choice of symbols?