A chilling horror novel about a haunting, told from the perspective of a young girl whose troubled family is targeted by an entity she calls “Other Mommy,” from the New York Times bestselling author of Bird Box. To eight-year-old Bela, her family is her world. There’s Mommy, Daddo, and Grandma Ruth. But there is also Other Mommy, a malevolent entity who asks her every day: “Can I go inside your heart?” When horrifying incidents around the house signal that Other Mommy is growing tired of asking Bela the question over and over, Bela understands that unless she says yes, her family will soon pay. Other Mommy is getting restless, stronger, bolder. Only the bonds of family can keep Bela safe, but other incidents show cracks in her parents’ marriage. The safety Bela relies on is about to unravel. But Other Mommy needs an answer.