The Creature in the Crystal — J.A. Darke

As a little kid, Val was intrigued by anything to do with the supernatural. So when her cousin Ronnie comes to visit for a long weekend, with a book of spells, a Ouija board, and some mysterious gems in tow, Val's curiosity is reignited. But soon Ronnie's fearless spirit and sense of spooky fun starts to haunt Val, who keeps having nightmares and witnessing a monster following her around the house. Can the girls figure out the truth before they're forced to come face to face with a real-life haunting?