How to make a scary movie human, take a movie like Sinister....

How to make a scary movie human, take a movie like Sinister. How can I make that guy so real so that the scary elements of it are more scary and it functions as a genre movie - as the way it's supposed to, you want to hear a ghost story at midnight, that's a good one - but how do you fill it up with humanity inside, in staying true to the genre? You know? Does that make sense?