Isabella Laird Muir was born on 16 October 1891 in Blantyre Parish. She was the illegitimate daughter of Christina Muir, a cotton factory worker. Isabella's father's name was not listed on her birth registration. She had an older half-brother, William Gartshore, who was also illegitimate. Christina had another illegitimate daughter, who was named Elizabeth in 1897. It is not known if she was a full or half-sister to Isabella.
In 1901 Christina and her three children lived in Fore Row, which was housing for Blantyre Works employees. No occupation was listed for Christina at the time the census was taken. In 1905, Christina's younger sister died, leaving her husband, Joseph Barr, with three young children. Christina began keeping company with her brother-in-law and had a child with him in 1907. They married three years later. In 1911 the blended family lived at 293 Glasgow Road and Isabella was working as a weaver in a factory.
On 14 July 1911 Isabella Laird Muir married Charles Findlay at her mother and step-father's home. She and Charles had five children between 1912 and 1920. Isabella died on 8 February 1921 in the family's Burnside Cottage home, of myocarditis, which is often caused by a viral infection. She had been sick for four months before her death.
1901 Scotland Census, 31/03/1901 Muir, Isabella (Census 1901 624/00 006/01 026)
1901 Scotland Census, Parish: Blantyre; ED: 6; Page: 26; Line: 21; Roll CSSCT1901_246
1911 Scotland Census, 02/04/1911 Muir, Isabella (Census 1911 624/00 004/00 011)
Scotland, Select Births and Baptisms, 1564-1950, Isabella Lourd Muir, 1891
Scotland, Statutory Registrations, 1855-2013, 1891 Muir, Isabella (Statutory Births 624/00 0451)
Scotland, Statutory Registrations, 1855-2013, 1911 Findlay, Charles - Barr, Isabella (Statutory Marriages 624/00 0054)
Scotland, Statutory Registrations, 1855-2013, 1921 Findlay, Isabella Laird (Statutory Deaths 624/00 0026)