Are you seriously telling me a typical grandma would let a stranger into the house in the middle of the night and instead of seeing what he's up to and make him leave, would rather go to sleep and leave him alone with your 16 year old grand daughter?
That's when the movie started to lose me. Logically it just made absolutely no sense. No grandma or any parent in their right mind would ever let a stranger into the house in the middle of the night and leave him alone with a minor especially a girl.