Bart and Krista Halderson were a seemingly happy couple living in Windsor, Wisconsin, with a beautiful home and two grown sons. But when Bart and Krista went missing over a July Fourth holiday weekend, authorities began looking for the couple, eventually finding them murdered and dismembered in various locations. As law enforcement zeroed in on a suspect, a clue on social media helped lead them to someone closer to Bart and Krista than anyone could have imagined. Stream the latest 20/20 ‘Road