Mystery of the Attic — T.J. Perkins

Melissa is just an average thirteen-year-old with a semi-average life until she moves into a nineteenth-century farmhouse. There she discovers that the house is haunted by two ghosts-one good and one evil. With the help of her stepsister, they unravel an age-old mystery and solve an unsolvable crime; one that was never intended to be solved. Many evil hauntings attempt to prevent the girls from discovering the truth. It's a race against time and a battle of wits to see which will prevail - the living or the dead.