Sister Joan Gibbons was a Sister of Mercy for 65 years. She was well known for her expertise in Mathematics which she put at the service of the community throughout her life. As a Mathematics teacher at Little Flower, Gwynedd Mercy Academy, and Merion Mercy Academy High Schools, the girls loved and respected her and knew that if they had Sister Joan, she would challenge them to do their best.
In 1971, she became the Treasurer General of the then Merion Community. Throughout the 25 years, she was treasurer, Joan placed the community in a stable financial position with progressive financial decisions.