Thirteen-year-old Catherine loves her eight-year-old brother David, but she doesn't love his autism. David's behavior frequently embarrasses Catherine and keeps her from socializing. So she comes up with a lot of rules for David to follow when they're together (a peach is not a fuzzy apple, no toys in the fish tank, hug Mom, not the video store clerk, and keep your pants on in public). Catherine thinks she's doing David and the neurotypical people around him a favor. Yet when she meets Jason, a boy who's lost his abilities to walk and speak because of an accident, Catherine learns valuable lessons about disability and normalcy. For example, she sees that Jason's picture board is severely limiting his communication, helps him add to it, and wonders how David must feel when he can't communicate what he wants or needs.
Catherine's growth as a character is great, but many parents and teachers may be turned off at David's portrayal. To wit, this character is autistic and little else. He is punished for exhibiting echolalia and other "autistic behavior" that is natural for him. Jason too is seen as disabled and not much else, which is not a good message for readers. It definitely bears discussion that people with disabilities are people first--and the rules they live by should be no more different from ours than absolutely necessary.