Fern Elizabeth Castle

Fern is Rose's sister, Nina's daughter, and Willow's mother. She apparently has some form of autism, though that word is not used explicitly. She is a librarian and thrives on routine. Throughout the novel, Fern is portrayed as absent minded and unreliable in some regards, though she is high functioning in her ability to live on her own and hold a job. This makes her seem an unreliable narrator until near the end of the novel when the author reveals that Rose has been lying about all the things Fern has forgotten.

Fern grew up with Rose and Ingrid, and she considers Rose to be her strongest supporter. She felt she could always depend on Rose to help her navigate social situations she did not understand on her own. When the girls were 12, they were camping with Nina's boyfriend Daniel and his son, 14-year-old Billy. Billy...