Content Warning: This section includes discussions of animal euthanasia.

William is the 11-year-old protagonist of The Summer of Riley. At the beginning of the novel, he is struggling with his grandfather’s recent death and his parents’ divorce. He, like many people, has a hard time Seeing Both Sides of an Argument. He often disagrees with his best friend Grace when her ideas contradict his, and he cannot understand his parents’ separation, seeing it as evidence that they put their personal needs over his. Some of William’s misunderstandings are the result of his own stubbornness, but others are caused by a lack of information. Neither of William’s parents is willing to tell him the truth about their new romantic relationships, leaving him to fill in the blanks as best he can. He has to resort to eavesdropping on his parents’ conversations to learn what is happening between them, and this results in feelings of mistrust and betrayal when he knows that his parents are keeping things from him. 

William was very close to his grandfather and struggles with feelings of sadness and loneliness ever since his grandfather died. William’s mother decides to get him a dog in the hopes that it will help him process his grief.