Incidents in Our House. Josh Malerman

For eight-year-old Bela, her family is her whole world. There is her mom, dad, and Grandma Ruth. But there is also another mom, a sinister being who asks her every day: "Will you let me into your heart?" When horrific incidents at home show that the other mom is tired of asking the same question over and over again, Bela realizes that if she doesn't say yes, her family will have to pay. The other mom becomes more dangerous, stronger, bolder. Only family ties can protect Bela, but other incidents expose the cracks in her parents' marriage.