Mary Cassini, born in Canterbury in the UK, was a child actor before becoming a cadet newspaper reporter, then training in fine art. Immigrating to Melbourne with her family in 1958, Mary continued acting in theatre and films, becoming professional in 1973. In 2013, she was made Honorary Member of Actors Equity division, MEAA.
In the 1970s, Mary began weaving tapestries in the studio she shared with her husband Peter Stapleton, also a weaver. Mary has travelled the world as a peace ambassador.