McNatt-Chiappetta left her family's residence in the 900 block of Van Kirk Street in Clairton, Pennsylvania on November 5, 1981. She was headed to an evening rally at her high school, which was located about two blocks from her home. McNatt-Chiappetta was last seen walking on Miller Avenue and Mitchell Avenue at approximately 7:15 p.m. She never arrived at the rally and has not been seen again.

The police initially believed McNatt-Chiappetta ran away, but they began to consider other theories after days passed without contact. Foul play is suspected in her case. McNatt-Chiappetta's mother never believed her daughter ran away from home; she stated it wasn't in her personality. Her mother described her as a talkative, responsible tomboy. She was an eighth-grader at Clairton High School in 1981, an average student. She volunteered at her church and baby-sat, and she enjoyed baton twirling, swimming and dancing.

Authorities planned to question Dean Maksin, a former friend and neighbor of McNatt-Chiappetta's family, in August 2001 regarding her disappearance. Maksin was charged with sexually assaulting another woman in the area in 2001. Investigators interviewed Maksin after Chiappetta vanished in 1981, but he was not considered a possible suspect until after his arrest for the unrelated charge 20 years later. McNatt-Chiappetta's family said that she would have trusted Maksin at the time of her presumed abduction. There have been no arrests in McNatt-Chiappetta's case; it remains unsolved.