Promises to Keep by Ann Tatlock tells the story of Rosalind Anthony (Roz) and her family, who have just moved to Mills River, Illinois to escape an abusive situation. Days after the family settle into their new home they are surprised to find the previous owner Tillie Monroe, on their front porch reading the newspaper. Even though Tillie’s sons have sold the house and sent her to her to a facility for the aged, she manages to find her way home day after day and is determines to die in the place she has lived her life in. The family feel sympathy for Tillie and Roz’s mum allows her to move back into the house.

Roz meets a girl called Mara, who becomes her first friend in Mills River, who are both very different, but discover they have something in common that binds them together. The girls are both holding deep secrets and make a promise never to tell anyone else once they have told each other. Danger stalks the family that encourages Tillie to have the courage and selfless love in her determination to protect the family she has adopted as her own.