The Night Gardener by Jonathan Auxier
My rating: 4 of 5 stars
Two Irish orphans find themselves in the English countryside looking for work, when they are hired to be servants at a creepy mansion no one will go near. A giant black tree has become a part of the house and something keeps opening the front door at night. The family has a secret and the siblings soon become part of an ancient curse that threatens their very lives. Deliciously creepy and fantastically written this story will stay with you long after the pages are read.
The DC Public Library has this book in both book and ebook formats - check it out!