The fifth daughter of the 2nd Baron Redesdale, Mitford grew up in England with her brother and five sisters, one of whom was the novelist Nancy Mitford (Mitford, Nancy). She moved to the United States in 1939, became a naturalized U.S. citizen in 1944, and began to write in the late 1950s. Her first published book, the autobiography Hons and Rebels (1960; U.S. title Daughters and Rebels), is an entertaining account of her childhood, her eccentric family, and her early adult life. Mitford's second book, The American Way of Death (1963), a caustic examination of unscrupulous practices in the American funeral industry, became a best-seller. Her long-standing interest in civil-rights cases found expression in the book The Trial of Dr. Spock (1969), an account of the famous pediatrician's trial on conspiracy charges for antiwar activities during the Vietnam War. Kind and Usual Punishment: The Prison Business (1973) is Mitford's critical examination of the American prison system. In 1992 she published The American Way of Birth about the state of American obstetrical care. A Fine Old Conflict (1977) is mainly an account of her experiences as a member of the U.S. Communist Party in the 1940s and '50s.