Unity Mitford summered at the Berghof where she continued to discuss a possible German-British alliance with Hitler, going so far as to supply lists of potential supporters and enemies. At the 1939 Bayreuth Festival, Hitler warned Unity and her sister Diana that war with Britain was inevitable within weeks and they should return home. Diana returned to England, while Unity chose to remain in Germany, though her family sent pleas for her to come home. After Britain's declaration of war on Germany on 3 September 1939, Unity was distraught. Diana Mitford told an interviewer in 1999: "She told me that if there
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