Margaret Gelletly was born in 1818 in Perthshire, Scotland to parents John Gelletly/Gellatly and Christian Adam. She married Alexander MacKenzie Allen/Allan on 6 June 1840 in Kinfauns, Perthshire. They had the following children: John Gellatly Allan (1840-1927); Elizabeth Galletly Allan (1842-1917); Margaret Ann (born 1843 – died 18 April 1854 on the Eureka Diggings aged 11 years); Robert (1847-); James (born 1847 – died 18 October 1848 aged 18 months at Alloa, Scotland); David McPherson Allan (1849-); Jessie (born 1852 – died 26 December 1852 Geelong aged 6 months); Esther Ann Allan (1855-1903); Georgina Rennie Allan (1858-1929); and Margaret Bathgate Allan (1861-1935).

The 1851 Scottish Census lists the Allan family at 29 West Port,  Dundee, in the County of Angus. Alexander aged 30 was described as a sailor, with his wife Margaret aged 32 years. Living with them in the household was Jannet Gelletly aged 34, Ino Scott, 17 years, John Allan 10, Elizabeth Allan 8, Margaret Allan 6, Robert Allan 4 and David Allan, a one year old. Margaret and Alexander emigrated from Scotland on the Flora in 1852, arriving at Point Henry (Geelong) on 23 October 1852.

Margaret (Gelletly) and her husband Alexander McKenzie Allen were in Ballarat at the time of the Eureka Stockade, and possibly living on the Eureka Diggings. By 1863 they were living at Drummond Street, Ballarat West. According to the Ballarat Old Cemetery registers Margaret Gellatly Allen died on 4 January 1863 aged 44 years, and was buried on 5 January 1863 (Grave CN 19 6).  Her husband Alexander died in September 1899 and was buried at Mount Egerton Cemetery.

Scotland, Select Births and Baptismsm 1564-1950; 1851 Census, p. 14, Household schedule number 43, line 8, Roll CSSCT1851_60; Dorothy Wickham, Women of the Diggings: Ballarat 1854, BHS Publishing, 2009; Ballarat Old Cemetery Records.