Prue Dempster was one of the 3 tutors housed University College (the residential College for Women) at the University of Melbourne. Mary joined the trio in 1958 when she began her year as Senior Demonstrator at the University and acted as tutor to the students residing in the college. Prue, a geographer, and Mary became firm friends and would hang out together as well as work together, both attending the May 1958 McCoy Society expedition to Wilson's Promontory.
It was through their friendship that Mary was invited to join the Central Australia roadtrip when at short notice the fourth member dropped out. Mary met with Prue, Lorna and Ady and a week later had rearranged her work and jumped in the VW camper to begin their month-long, 5700 mile Centralia road trip.