Found (movie, 2012)

Marty is the ideal fifth grader—he gets good grades, listens to his teachers and doesn't start trouble in class. But a darkness is beginning to fall over Marty's life, the kids at school won't stop picking on him, his parents just don't seem to understand him, and now Marty must grapple with a terrible secret that threatens to destroy life as he knows it—his big brother is a serial killer!