Missing - the Tracy Byrd and Mark Himebaugh cases

Tracy Byrd and Mark Himebaugh - two separate children - both walked off and were never seen or heard from again. Both stories are equally chilling. Tracy bird was 14 and possibly pregnant when she was last seen walking in the rain walking away from a Bucks County PA high school, her mother was found murdered 7 months later. Was the same person who murdered her mom the one who murdered Tracy? Mark Himebaugh was only 11 when a marsh fire started outside of his house. He went to wa...