“Now that Casley seems to be into these things, too, I feel like I don’t belong whenever the three of us are together.”

This passage introduces the main theme of Feeling Left Behind in Claire’s friendship with Casley. Even before she has to deal with a ghost, this rift in her friendship is one of the biggest problems in Claire’s life. The novel’s resolution shows that her loneliness is in fact the reason for the haunting.

“Get a grip on yourself, Claire. He’s not even talking about ghosts yet. And even if he starts, none of it is real. Sure, I used to think it was when I was little, but not anymore. I’m a scientist now. Scientists know better than to believe in things like ghosts.”

This passage shows how Claire uses her interest in science as a tool for Overcoming Fear, especially her fear of ghosts. She believes that science can help her find rational explanations for things that frighten her. Although it turns out that ghosts are real, Claire will still be able to use the scientific method to investigate the mystery. Claire’s stern language to herself shows how she hasn’t learned to acknowledge her feelings and show self-compassion, part of her character’s development.

“The next fifteen minutes are boring, since traffic is moving like a turtle and Dad is droning on about some disaster involving a boat called the SS Eastland. Apparently, it sank in the Chicago River right at the intersection of LaSalle Street and Wacker Drive. A lot of people drowned.”

This is an example of the novel’s use of foreshadowing, especially as a clue for the mystery plotline. This detail is mentioned casually among other tragic disasters in Chicago’s history. Claire does not know it yet, but the SS Eastland is the key to solving the mystery of boy 396.