Born in Qingdao or Shanghai, China, Mary Jane Reiss was the youngest daughter of Hugo Reiss (1879–1931), a prominent Jewish businessman who emigrated to the USA in 1896; he was an executive at his family's British fabric-and-small-arms wholesale firm, G. Reiss & Co. Ltd. and served as Brazil's consul in Shanghai. Hugo Reiss married, at The Grand Hotel in Yokohama, Japan, on 16 October 1911, Marie Ignatius Murphy (1891-1965), an Irish Roman Catholic native of San Francisco, California; she was a daughter of James. J. Murphy and his wife, Mary O'Gorman.