Mrs. MacKinnon served from 1965 to 1995 as a Nursing Sister in the Royal Canadian Army Medical Corps and the Canadian Forces Medical Services. She has been a member of the Royal Canadian Legion for 37 years, and received a Life Membership from Branch 1 (Charlottetown) in 2007. In 1970, Mrs. MacKinnon recognized that there was a need to support Veterans with disabilities so that they could also parade during Remembrance Day services. This recognition prompted Mrs. MacKinnon and another Legion member to provide transportation for these Veterans. Each November, from 1982 until 2011, Mrs. MacKinnon organized remembrance services in four nursing homes in the Charlottetown area, which involved setting up indoor cenotaphs for ecumenical services including a choir and music. On top of this work, since 1982, Mrs. MacKinnon has also acted as the pianist for Legion services, during which time she developed wartime songbooks in large print.