In the summer of 2013, Minnesota resident Gary Herbst seemingly vanished. But before anyone realized he was missing, neighbors noticed something strange: late one night, they watched a rolled-up carpet being carried out of his home. Years later, investigators would uncover a startling discovery that revealed what really happened. In an exclusive interview, 48 HOURS correspondent Peter Van Sant speaks with Gary Herbst's son, Austin Herbst, about why he killed his father.