Mary Eleanor Underdown was born 14 October 1872 in Port Adelaide, South Australia, Australia to Thomas Underdown (1821-1876) and Rachel Harpur (c1829-1904) and died 3 March 1936 13 Heath street, Birkenhead, South Australia, Australia of unspecified causes. She married Magnus Petrie Irvine (1866-1934) 23 December 1891 in Adelaide, South Australia, Australia.
|Offspring of Magnus Petrie Irvine and Mary Eleanor Underdown (1872-1936)|
|Magnus Thomas Irvine (1895-1968)|
|Helen May Irvine (1898-1969)|
|Norman Kenneth Petrie Irvine (1900-1974)|
|Lorna Irene Lawder Irvine (1902-1974)|