Mary was last seen in Lake Odessa, Michigan sometime during 1965. Her oldest son, Donald McLaughlin, who was eight years old in 1965, recalls that his mother visited him at school and told him she was going away for awhile but would eventually return. Mary apparently traveled to her sister's home in Muskegon, Michigan afterward, and left a photograph there. She disappeared afterwards and has never been heard from again. Donald filed a missing persons report for his mother in 2002, thirty-seven years later.

Donald and some of Mary's neighbors stated that she was having marital problems in 1965. Donald described Mary's husband, his father Carlon Arden McLaughlin, as a violent man. Carlon and Mary fought frequently and it was alleged that Mary had extramarital affairs. Carlon moved to Mississippi after his wife's disappearance. Donald believes his mother left of her own accord, but was was murdered sometime afterwards.

Mary has five children. She was sent away by her family at the age of eight and lived with several foster families, including Carlon's parents, until her marriage. She is a 1957 graduate of Lakewood High School. There has been no activity on her Social Security number (SSN) since around the time she vanished, and identity and public record checks have turned up nothing either. Investigators believe Mary either died long ago, or changed her identity so completely that she cannot be found. Her case remains unsolved.