Overview of Mary Oliva
Sometime between 20.00-21.00 on the night of July 28, 1973, Mary Oliva and her husband Frank left their house in their 1958 beige Chevrolet and drove away. They were never seen again. They were reported missing on August 3, 1973, by their son.
Nothing had been disturbed at their home, and the front door was closed, but not locked. Mary Oliva left behind her purse, which she always carried, and her medicine.
The couple was declared legally dead seven years after they disappeared, though their bodies were never found. (Information retrieved from NamUs.gov)