Bun loves baseball in general and the Phillies in particular. (And he's a true fan because he even loves them this year.) He's been learning a lot about the game through his baseball practices, and he's doing his best to pass that passion on to Septimus. He is starting by reading his "Phillies' ABC" book to his little brother.
I don't know if Septimus will love baseball, but he sure loves his brother. Look at the way he smiles and wiggles while Bun reads to him.
Brothers and baseball are the best.