 Muir was born in India to G. B. F. (Basil) Muir and Gladys Helen Mary, and spent the first 10 years of her life there.Until moving to Europe in 1930, Muir had no formal education and was educated by her mother.At the age of 10, Muir began her general education at a boarding school in Montreux, Switzerland and at the Downe House in Berkshire, England.