Mary Stewart-Mackenzie was born in Munich, the daughter of Stewart-Mackenzie of Seaforth. She married, firstly, Col. the Hon. Constantine Stanley, and secondly, in 1881, the barrister Francis Henry Jeune.
Mrs Jeune was a journalist, socialite and charity worker, known to JW in London society in the late 1880s.
Who's Who, 1898, London, 1898.