Seven-year-old Diana and her two-year-old half-brother, Mark Eugene Yoli, were last seen on their way to the playground at Camp Lejeune, North Carolina at approximately 3:15 p.m. on September 13, 1962. Diana's stepfather and Mark's biological father (who was a Marine Lance Corporal) was stationed on the base.
The children's parents were initially not concerned when they didn't return to their home in the 700 block of Butler Drive because they were known as adventurous children who tended to wander. An extensive search of the area, lasting four days, turned up no sign of either Mark or Diana.
Convicted child molester Henry Morris Hunt, who died in 1991 at the age of 85, is the only suspect in the children's presumed abductions.
On her deathbed in 1992, Hunt's wife told her daughter that Hunt dumped Mark and Diana's bodies in a mine shaft near Maysville, North Carolina. Hunt reportedly told his wife that he'd picked up Diana & Mark at Midway Park, took them fishing and said that Mark accidentally drowned and he panicked afterwards and killed Diana.
In 2011, bones were found underneath the demolished home that was once owned by Hunt, and the authorities thought they'd found the children's remains, but the bones turned out not to be human.
Mark and Diana's cases remain unsolved and foul play is suspected.
Mark is described as having dark brown hair, brown eyes, a stocky build and an olive complexion, last seen wearing a t-shirt and brown shorts. Diana is described as having blonde hair, blue eyes, last seen wearing a print blouse and shorts.