The main character, Brent, changes over the course of the novel. He begins as a self-centered teenager concerned with impressing others. He makes immature choices, such as drinking underage and driving under the influence. He is not a likable character at the start of the story.
After Brent's journey to the four corners of the United States to set up whirligigs in honor of Lea, Brent develops more self-esteem. He starts to enjoy new things, such as reading and creating. He is no longer self-pitying. Brent becomes more mature and likable.
The whirligigs Brent makes have an impact on other characters featured in chapters of the book. In California, Jenny is a teenager who takes care of her elderly and sick Grandmother. Jenny is conscientious, albeit anxious, and is told by her mother that she is too serious. She sees the whirligig on a drive with her Grandmother. Jenny starts to change her perspective and gains a sense of hope and joy.
Stephanie has a similar experience with the whirligig she sees. Stephanie is sarcastic and pragmatic, but the whirligig helps her believe in love, hope, and joy.
Mrs. Zamora wanted Brent to make the whirligigs so
people all over the country receive joy from her even though she's gone. You make the smiles that she would have made.
We can see how the characters receive this joy and change over the course of the story.