It's interesting reading Zusak's work "backwards" and seeing how much he has developed as a writer between his Wolfe brothers trilogy and The Book Thief. The strength of these books is definitely Cameron's voice and the fullness of his character. He is a rough, working class kid with a good heart and love for his family that shines through. Underdog was a slower, coming-of-age type book without much of a clearly defined plot, whereas Fighting Rubén Wolfe uses an illegal amateur boxing competition as the vehicle to explore brotherly love more deeply. This kind of raw but positive sibling relationship is rare in modern YA, and a pleasure to read. I did find bits of purple prose, over explaining and more boring sections, but overall these were a worthwhile read and I'll likely pick up #3 soon.