Joan was the daughter of Thomas Aloyious McMahon and Catherine Cecile Horan. The date and place of her birth have not been found.
Joan McMahon
Thomas Aloyious McMahon (1904-1971)
Thomas Francis McMahon (1862-1907)
Stephen McMahon (1826-1879)
Catherine Kennedy (1836-1915)
Hellen Nellie Frances McGrath (1866-1938)
Robert Michael McGrath (1826-1889)
Catherine O'Grady (1835-1913)
Catherine Cecile Horan (1907-1992)