Mary Campbell was born in Montreal into a large extended Scottish immigrant family. She was the eldest of four children. She grew up in the east end of Montreal during an insecure and lean time. Mary was famous for her speed and accuracy as a civilian teletype operator in WWII for the armed forces at Dorval Airport. Mary married Lewis Campbell in 1948, and together they had two children. Mary became a stay-at-home mother for most of the 1950s during which there were long summers at a cottage in the Laurentians. Mary loved sweets and she perfected her creations of fudge, Nanaimo bars, and Hello Dollies. Oakville became her home in 1962 when they moved for Lewis's refinery startup job with Shell. Mary spent the remainder of her working life with the Halton Board of Education as a school secretary first at Purdue High School and then at Eastview Public School. She travelled extensively with Lewis in their retirement. Mary was active in the Presbyterian church and the Eastern Star. She delivered meals on wheels and was a dedicated Oakville Trafalgar Memorial Hospital volunteer for over 20 years. She was a prodigeous knitter and crocheter producing many touques, mittens and blankets for family and charitable organizations. She played bridge and loved to dance, starting with the jitter bug in her youth. In later years her memories left her and she lived happily in the moment.

Mary was predeceased by her husband Lewis, her parents, Helen and James Garner, her stepfather Ed Mustill, her sister Margaret, her brothers George and Albert, and her son-in-law Sidney. She is survived by her son, Brian, his wife Joanna, her daughter Brenda, grandchildren Alexander, Elizabeth, Mackenzie, Hendrik, and Juliana, and great grandchildren Isla, Stella, Millie, Alaina, and Mila.