Going in, I knew this 1978 novel would feature a boy "confined" to a wheelchair who "suffers from" cerebral palsy. But Sam is a pretty good character in many ways. He's confident and popular, and generally at ease with his disability.
The story is really about Liz and her relationship with her parents after her brother's death. She has realized she doesn't like who her parents are as people, that they're phony, put too much value on appearances.
Be warned; it's not a romance, and it's not particularly happy. I was a bit thrown by the ending, but I'm happy overall with Sam and Liz as a pair of kids who feel on the outside of things, together.