Monica Coulter was born on 30 August 1926 at 12 Glasgow Street, Ardrossan. She was the daughter of Frank Coulter (1895-1976) and his wife Sarah McKerracher (1895-1972). She had a sister Mary (1924-1978) and a brother Frank.

Monica was educated at Saint Mary's School Saltcoats and the Central School, Ardrossan where she was dux medalist in 1939-40.

Along with her family, Monica attended the opening of the Church of Saint Peter in Chains on 2 October 1938.

Monica became a postulant Carmelite nun on 8 September 1943 adopting the name Sister Mary of Saint Joseph. She was clothed in the Carmelite habit on 14 March 1944 and made her first profession on 14 March 1945. She made her final profession in 1948. All of these events took place at the Carmelite Monastery, Dumbarton.

Sister Mary died in the Carmelite Monastery, Dumbarton on 25 September 1975. She is buried in the Carmelite plot in Dumbarton Cemetery. May she rest in peace.

The photograph on the right was taken in April 1974.