This book definitely seems like it will be a fast-paced, thrilling ride! I love books with a “babysitters being stalked” type trope...it brings me back to “the person is calling from inside the house” urban legend from my teen years. I like the fact that this book seems to deal with family issues between the two sisters as well. That will add an extra aspect of character development that I think I’ll love. The cover isn’t my favorite but the title intrigued me right away.