How does the author use allusion in the novel, What Happened to Rachel Riley?

Wonder is a book about the bullying of a boy who does not deserve it. It also contains a plot twist in which an otherwise nice kid makes a bad decision and hurts others. These are symbolic of the plight Rachel experiences in What Happened to Rachel Riley? because Rachel is ostracized, a form of bullying, and she is the victim of a good person who made a bad choice. She reads this book at the beginning of the novel.