When 12-year-old Ruby's mother is called to serve in Afghanistan the family must move in with her grandmother to a house filled with secrets. Lonely and missing her mother terribly, Ruby struggles to fit in at her new school, revealing her heart in the secret lists she keeps. Her worst fears are realized when her mother is wounded, leading Ruby to discover both her true friends and the unexpected answer to an old mystery, one that brings more than one longed-for reunion to the beleaguered family.