Park, but found herself bored with English country life. Tree and most of his friends were Conservatives, and Democrat Marietta again found herself politically isolated. Their daughter Penelope was born in 1949. Short of money, Tree sold Ditchley and agreed to return to New York City with Marietta, her daughter Frances Fitzgerald and their own daughter, future '60s fashion model Penelope Tree, and his butler Collins. Politics and Adlai Stevenson Marietta Tree immediately joined the Lexington Democratic Club, and two years later was elected the county chairwoman. She was elected to the Democratic State Committee in 1954. Tree began an affair with Adlai Stevenson in 1952, the year of his first unsuccessful presidential campaign. Perhaps related to his bisexuality, Tree’s husband was unfazed by the affair and even invited Stevenson to the couple's homes in New York, Barbados and London. They continued their affair through his unsuccessful 1956 presidential campaign. Afterward, however, Stevenson began to take other lovers. Tree also retained a connection to Huston, who gave her a role in his 1960 movie The Misfits. At the same time, John F. Kennedy named her the United States Representative to the United Nations Commission on Human Rights, where she was able to work directly under Stevenson, who had been named head of the American delegation. She served in this position from 1961 to 1964. On July 14, 1965, Tree and Stevenson were walking in London when he suffered a heart attack, and later died at St George's Hospital. That night in her diary, she wrote: "Adlai is dead. We were together." Later life She and her husband remained married, though estranged. Ronald Tree died of a stroke on July 14, 1976, in London, while Marietta was in New York. Her affair with English architect Richard Llewelyn-Davies ended with his sudden death in 1981. Tree supported herself in later years by getting herself appointed to some well paid directorships, including the boards of CBS, Pan Am, and Lend Lease Corporation of Australia. She also served as women's trustee on the board of the University of Pennsylvania. In 1987 she appeared in the Danny Huston film Mr. North, released about a month before John Huston died of emphysema on August 28, 1987. Death Tree died of breast cancer on August 15, 1991, at her home in New York. Character Isaiah Berlin characterized her political standing as "a progressive, liberal figure who was