Miller was dropped off at a bar in Milton, Pennsylvania during the morning hours of July 1, 1989. She was planning to attend the wedding of a friend later in the day and was carrying a gift, as well as her clothes for the event. She apparently attended the ceremony and was photographed there, though some accounts state that she never arrived at the wedding. Miller is believed to have returned to her home in Sunbury, Pennsylvania during the early morning hours of July 2. She resided on Penn Street with a former police detective who reported her missing. She has never been heard from again.

Prior to Miller's disappearance, she was a police informant and provided authorities with information about drug trafficking. She had received threats from people who warned him to stop talking to authorities or she would be killed. About two weeks before Miller went missing, she told investigators that the matter had been taken care of. It is unclear whether Miller's work as an informant or the death threats were related to her later disappearance.

Miller resided in Sunbury, Pennsylvania in 1989. She left behind a young son. Authorities searched several mines in Augusta Township, Pennsylvania during the years following her disappearance, and searched a pond near Trevorton, Pennsylvania in 2004. Investigators refused to divulge whether any evidence related to Miller's case was recovered. She is believed to be the victim of a homicide. She was declared legally dead in the fall of 2002. Authorities searched a pond for remains in 2004, but found no evidence.

Some agencies may list July 2, 1989 as the date of Miller's disappearance, which remains unsolved.