Louder Than Words by Jenny McCarthy
Until this book, I'd never read anything by Jenny McCarthy, and I think it was a good choice. She's not a great writer, but she's conversational, funny, and easy to read. Louder Than Words is the story of how her son was diagnosed with autism and what she did to make him better. The treatment and cause of autism can be fairly controversial, but she doesn't get too hung up on that, just shares her story.
An interesting recurring element in Jenny's story: two Mormon missionaries who keep showing up at her door. She doesn't "get" the church, but she treats them gently.