Daniel Morcombe: Tracking his KillerWATCH THIS: 60 Minutes goes inside the biggest murder investigation in Queensland's history and the largest child abduction case in Australia. On December 7, 2003 Daniel Morcombe was last seen waiting to catch a bus on the Sunshine Coast. Daniel was a beautiful young boy - trustworthy and punctual - so when he didn't come home that night, his parents Bruce and Denise knew something was wrong. His disappearance sparked Queensland's biggest and longest police case. Detectives pursued thousands of leads but as the days turned into weeks, and then months, the hopes of finding Daniel seemed extremely remote. The months turned into years but Bruce and Denise Morcombe never gave up searching for their boy, or looking for his killer, and in 2009 they began calling for a Coronial Inquiry. Finally they succeeded, and in 2011, the inquest began. It would be the turning point in the investigation as Police switched their focus to Brett Peter Cowan. Over the next six months investigators carried out a delicate and highly secretive undercover operation. It culminated with Cowan confessing to Daniel's abduction and murder, and leading detectives to his remains. Bruce and Denise had found their son and now his killer has been put behind bars