Melissa's mother, Alta Highsmith, advertised for a babysitter for her in August of 1971. At 7:30 a.m. on August 23, a woman who called herself "Ruth Johnson" answered the ad. Johnson and Alta made plans to meet each other at Alta's place of work, but Johnson did not arrive. She called Alta later, and was hired. She stated she had a nice house with a large backyard and cared for other children.

Johnson went to Alta and Melissa's apartment at Spanish Gate Apartments on on east Seminary Drive in south Fort Worth, Texas at 7:30 a.m. on August 23. Alta had already left for work, and Johnson met Alta's roommate instead. The roommate stated Johnson was well-dressed and wore white gloves. Johnson took away Melissa, some diapers and Melissa's pink dress and white sandals. When she did not return Melissa by 8:00 p.m. that day, Alta contacted the police.

A sketch of the babysitter is posted below this case summary. She has never been identified and Ruth Johnson was probably not her real name. Authorities believed the baby was taken by someone who wanted to raise a child, but this theory has never been proven. Both of Melissa's parents were investigated in their daughter's disappearance. They were divorced in 1971 and the child's father lived in Illinois. They subsequently reconciled and had three additional children before separating again in 1998.

No serious leads have ever been developed in Melissa's abduction, but the case was reopened in late 2005 at the request of her sister. Her case remains unsolved.

Above: Suspect Sketch