Rosemary was last seen working her part-time job at Dane's Country Store, a convience store at Highway 71 and Country Road 424 in Danevang, Texas, on November 24, 1990. She called her mother between 7:00 and 7:35 p.m. that evening from the store. The conversation terminated when Rosemary stated a customer had arrvived. Customers discovered the store was abandoned shortly after Rosemary phoned her mother. The store was unlocked and the television inside was turned on. Rosemary's vehicle, her radio and her other belongings, including her purse and paycheck, were still at the store, but there was no sign of her.

Authorities do not believe Rosemary left of her own accord. She was an honors student at the time of her disappearance and was excited because her older sister was about to bring over her infant for Rosemary to meet for the first time. There were some indications of a possible struggle inside the store: a soda machine that had been moved three to four inches from its normal resting place and one of its legs was bent, and there was a small dent on a filing cabinet. The cash register was found closed and no money or store merchandise was missing; robbery was evidently not the motive for Rosemary's apparent abduction. She had been working at the store for only a few weeks prior to her disappearance and was described as an ideal employee.

The day of Rosemary's disappearance, a local man took a Polaroid photograph of her. That picture was found sitting on the store counter after Rosemary's disappearance. The man, known as "One-Eyed Joe" because he wore an eyepatch, was questioned by the police and cleared as a suspect.

Rosemary enjoys dancing and listening to Spanish music. She did not wear makeup at the time of her disappearance, and she was very active in the Catholic faith. Rosemary resided in El Campo, Texas in 1990. She was a sophomore at El Campo High School, where she played the flute in the school band, and was a member of the National Honor Society. Her family stated she was extremely close to them and would not have left voluntarily. Her case remains unsolved.