The 'Edinburgh Wonder Worker'. Born in a poor tenement in Edinburgh, Sinclair was the daughter of a dust-man who worked for the City Corporation. She was educated at St. Anne's School in the Cowgate and went on to study at the Atholl Crescent School of Domestic Economy. She worked as a French polisher at the Waverley Cabinet Works. She was made redundant on the closure of the Works in 1918, but found employment in McVities biscuit factory. She entered a Convent of the Order of Poor Clares in London, as Sister Mary Francis of the Five Wounds, and brought relief and comfort to the poor of that city for a short time before she died of tuberculosis. Sinclair was buried at Kensal Green in NW London, but her remains were brought home to Edinburgh in 1927, being re-interred at Mount Vernon Cemetery in Liberton. Her remains were moved once again in 2003 to a shrine dedicated in her honour at St. Patrick's Church in Edinburgh's Cowgate.
Known as a kind and caring woman, many miracles have since been attributed to her and she was declared 'Venerable' by the Vatican in 1978. Cardinal Gordon Gray (1910-93), the Archbishop of Edinburgh and St. Andrews, declared that she could be one of the first Saints to come from the shop floor. A Margaret Sinclair Centre opened in Rosewell in 1965.