US Weekly claims to have photographic evidence that Kristen Stewart is cheating on 26-year-old boyfriend/co-star, Robert Pattinson, with Huntsmen director, 41-year-old Rupert Sanders. Nothing but bad news for Sanders, who is a married man & father of two. News of the infidelity might also take a toll in ratings for the upcoming “Twilight” movie, “Breaking Dawn Part 2″. This might be one awkward premiere! Pick up the issue of US Weekly this Friday to see pics!