By all accounts, 34-year old Paige Birgfeld was a devoted mother to her three young children. So when she suddenly disappeared last June, police in Grand Junction, Colorado suspected foul play. But while police and volunteers searched for the missing mother of three, disturbing evidence of a secret life she led shifted the investigation in a totally new direction. Did that secret life-which Paige kept hidden from her family-play a role in her disappearance? Harold Dow reports for 48 Hours.