Vanwinckle was last seen in the 400 block of Gibson Avenue in her hometown of Bethany Beach, Delaware sometime during June 1994. She has never been heard from again. Her vehicle was found in the parking lot of Rose's Department Store in Millsboro, Delaware about a week after she was reported missing.

Vanwinckle's live-in boyfriend did not report her missing; the report was filed by another close friend. Investigators found this suspicious and searched Vanwinckle's residence after her disappearance was reported. Two bedrooms inside the residence had bloodstains, leading authorities to declare Vanwinckle's case a homicide.

The prime suspect in Vanwinckle's disappearance committed suicide two months after her disappearance, but investigators still hope to resolve her case and recover her remains.