Deborah Cavendish, Duchess of Devonshire Deborah Cavendish, Duchess of Devonshire Deborah Vivien Cavendish, Duchess of Devonshire, (born Deborah Freeman-Mitford and latterly Deborah, Dowager Duchess of Devonshire; 31 March 1920 – 24 September 2014) was an English aristocrat, writer, memoirist and socialite. She was the youngest and last surviving of the six Mitford sisters, who were prominent members of English society in the 1930s and 1940s. Known to her family as "Debo", Deborah Mitford was born in Asthall Manor, Oxfordshire, England. Her parents were David Freeman-Mitford, 2nd Baron Redesdale (1878–1958), son of Algernon Freeman-Mitford, 1st Baron Redesdale, and his wife, Sydney (1880–1963), daughter of Thomas Gibson
Diana Álvares Pereira de Melo, 11th Duchess of Cadaval the history of the Portuguese monarchy, which she publishes under the name of Diana de Cadaval. "Dona" Diana's father was married twice, but only the second marriage was a religious ceremony. Diana has two older half-sisters, an older half-brother (born from her father's extramarital relationship) and a younger sister: When the Duke died in 2001, the eldest daughters of both marriages, Rosalinda and Diana, disputed the family heritage. "Dom" Duarte Pio, Duke of Braganza recognized Diana as 11th Duchess of Cadaval (on a non-hereditary basis, as all holders of the Dukedom of Cadaval in the past have obtained royal recognition