Rose is Rain Reign’s 11-year-old protagonist who has been diagnosed with high-functioning autism. She is portrayed as sensitive both to her environment, becoming overstimulated and overwhelmed by ambient noises such as those of a laptop or television, and emotionally, picking up on the tense dynamic between Wesley and Weldon. She experiences deep love for her dog, Rain, but is motivated to give the dog back to her old owners when she discovers that they lost her. This act suggests that Rose is more than capable of understanding and expressing a wide range of emotional experiences including empathy, camaraderie with others, grief, and loss. It should be noted that some representatives within the disabled community view expecting universal conformity to neurotypical emotional reactions and expressions as oppressive; see Samantha Stanko’s review of the book Mockingbird for more on this topic. Rose is also aware of the potentially abusive and borderline negligent behavior of her father but struggles to fully articulate the fear that his alternating anger toward and disinterest in her causes.

Rose has a strong interest in homonyms, which Martin uses as an example of the fascination some people with autism experience about certain topics.