The Whispers in the Walls by Sophie Cleverly

When the walls begin to speak, it is unwise to ignore what they have to say…

At the bidding of their cold-hearted stepmother, twin sisters Scarlet and Ivy are sentenced to board for a year at Rookwood School. The headmaster is cruel, the hallways are drafty, and there seems to be a thief afoot. When the finger of suspicion is pointed at Scarlet, she’ll do whatever it takes to clear her name–including some late-night detective work. But in the darkness of Rookwood, mysteries of the past come to light. The walls are talking of secrets past, and it’s up to Scarlet and Ivy to listen to their story…