Mullins was last seen in Mineola, Texas on December 12, 1981. She was going to a Christmas party with a male acquaintance, and disappeared after he picked her up. He is the last person known to have seen her. The party was at a restaurant called Arnold's, across the street from the garage apartment where Mullins lived. Her only surviving relative is her sister. She stated Mullins had gotten involved with a rough crowd prior to her disappearance. She has never been heard from again.

Kevin Leon Kirbo is the prime suspect in Mullins's disappearance. He is currently serving a life sentence for the 1995 murder of a Rains County, Texas woman. Authorities began searching a site along the Sabine River near Mineola, Texas for Mullins's remains in May 2010. They stated information provided by Kirbo lead them to that location. Her disappearance remains unsolved.