The whirligig Brent builds in Maine is the largest and most intricate of the four. He stays at a campsite which is described as peaceful and calm. By this point in the novel, Brent is ready to face what he did, the consequences of his actions, and the changes in his life. The whirligig he builds in Weeksboro has pinwheels, shells, spinning arms, and Lea's face. All the decorations and the whirligig's size symbolize all the things he's learned, and there is a culmination for him in Maine.
When Brent meets the artist, he is ready to talk about the accident. Initially, he makes the journey for Mrs. Zamora and Lea, to make up for, or atone for, what he has done. But the journey is his path to finding forgiveness, both from others and from himself.
He can face his future without the fear and insecurity he had before the accident. Lea, a stranger he never met, changes his life. The whirligigs he leaves change the lives of other people who see them.