I found Rules by Cynthia Lord to be very believable and very relatable even though I have never had a person with a disability involved in my daily life. The interview with Cynthia at the end of the book really made me appreciate the story that much more because she has a son with autism.
This is one subject that I feel like you have to have firsthand experience with in order to write about it truthfully.
Catherine seems selfish but she is twelve years old and just wants a normal life for once. At this age image and other people’s opinions about her seem like the most important. So when Ryan and Kristi judge her because of her brother David’s disabilities, she finds it unfair. I find her character very believable because I know when I was at that age I had the same priorities. However, I did not have the same responsibilities so I can empathize with her.
I think this is a must read for young adults to “help readers feel less afraid and more understanding towards people with disabilities in their own communities and schools.”
Jaycie Cheatham 
I liked this book a great deal, too. I have a ten-year-old daughter and the outlook Catherine has — I want to be liked; I want to do the right thing — rings true.
Yes, and being liked and doing the right thing often times are conflicting. So, I don’t think that Catherine was a bad person in this book. She’s only trying to find her own place.