The Grave Keepers by Elizabeth Byrne

Lately, sixteen-year-old Athena Windham has been spending all her spare time in her grave.
Her parents-owners of a cemetery in Upstate New York-are proud of her devoutness, but her thirteen-year-old sister, Laurel, can't understand it. Laurel hates her own grave. It's so boring and chilly down there. She'd rather spend her time exploring the acres and acres of state forest that surround the Windhams' property.
The Windham girls lead pretty secluded lives-their older sister died in a tragic accident the year before Laurel was born, and their parents' protectiveness has made the family semi-infamous in their small town.
As the new school year begins, the outside world comes creeping in. Athena-a professional high school loner-grapples with a newfound enemy and, even more surprising, her first best friend. And homeschooled Laurel, sheltered and shy, finds herself face-to-face with a runaway boy who's hiding out in an abandoned grave.
All the while, a ghost hangs around the Windham house and cemetery-the only grave keeper never to cross over, as far as she knows-messing with people's graves, turning the Windhams' lights off and on, spying on the sisters, and plotting how to keep the girls close to home and close to her . . . forever.
The Grave Keepers  is a unique coming-of-age story from talented debut author Elizabeth Byrne.