Here's the publisher's description:
From Newbery Honor author Ann M. Martin, who wrote the Baby-sitters Club series, comes a New York Times-bestselling middle grade novel about a girl, her dog, and the trials of growing up in a complicated and often scary world.
Rose Howard is obsessed with homonyms. She's thrilled that her own name is a homonym, and she purposely gave her dog Rain a name with two homonyms (Reign, Rein), which, according to Rose's rules of homonyms, is very special. Not everyone understands Rose's obsessions, her rules, and the other things that make her different—not her teachers, not other kids, and not her single father.
When a storm hits their rural town, rivers overflow, the roads are flooded, and Rain goes missing. Rose's father shouldn't have let Rain out. Now Rose has to find her dog, even if it means leaving her routines and safe places to search.
Like last week's review here, this novel is one that absolutely everyone needs to read to be a knowledgeable person. Rain Reign's main character and narrator, Rose, has Asperger's disorder, a relatively mild form of autism. Rose's obsessions with homonyms and prime numbers express themselves when she randomly blurts facts out while stressed or cannot stop talking about her obsessions in conversations, usually those that Mrs. Leibler, an adult who accompanies Rose during the school day, encourages her to participate in. Rose's actions, which she cannot really explain, and her struggles at school (she is bullied by several of her classmates and also is distracted by most noises, such as the fan of her teacher's laptop) will help readers, as they helped me, to understand more about how the minds of people with Asperger's disorder or more severe forms of autism operate and how these people certainly still have thoughts and feelings like those of anyone else. This story is also one of poor parenting, as Rose lives alone with her father, whose experiences first with an abusive father and later as a foster child with his brother and Rose's uncle, Weldon, make him both determined to provide for Rose without help and unstable, unable to understand Rose's issues, and, on rare occasions, even violent. The author, Ann M. Martin (author of another book I recommended here), does a good job of balancing the idea that Rose's father just makes occasional mistakes with the idea that he is not able to remain stable and act as a father for Rose. Rose's Uncle Weldon acts as a counterbalance to his brother, always being kind to Rose and trying to participate in her hunt for new homonyms. Finally, a review of Rain Reign would not be complete without mentioning Rain, Rose's dog in the story (whose name she chose because of its two homonyms, reign and rein). Rose looks to Rain for comfort and friendship, but her father accidentally lets her run during a major storm, leaving Rose to try and find her. Rain ends up not being dead, but what Rose does find out about her forces her to make a hard choice. Rain, Uncle Weldon, and the occasional kindness of Rose's classmates (usually from a girl named Parvani) prevents the story from being too depressing to actually be read. Rain Reign is a touching, painful, wonderful story that will change the way people think about mental disorders and will be remembered by every single one of its readers.