||Ava Alice Muriel Astor was born on July 7, 1902, the only daughter of John Jacob "Jack" Astor IV and Ava Lowle Willing. Her paternal grandparents were William Backhouse Astor, Jr. and Caroline Webster Schermerhorn, while her maternal grandparents were Edward Shippen Willing and Alice Barton.|
Ava Astor married Prince Sergei Platonovich "Serge" Obolensky, son of General Platon Sergeyevich Obolensky and Maria Konstantinovna Naryshkina, on July 24, 1924 in the Savoy Chapel in London. The marriage was considered the event of the season in England that year. Her brother Vincent gave her a Palladian Revival stone residence on his estate near Rhinebeck, New York. The house was north of his own "Ferncliff Casin" ("Astor Courts") and also overlooked the Hudson River. Ava named it "Marienruh" and retained it through her life. They had a son Ivan (born May 15, 1925) and a daughter Sylvia (May 18, 1931 — June 27, 1997)
After divorcing Serge in 1932, she married Raimund von Hofmannsthal (1906 — March 20, 1974), son of Hugo von Hofmannsthal and Gertrud "Gerty" Schlesinger. The couple was married on January 21, 1933, in the city court of Newark, New Jersey. The couple had a daughter, Romana von Hofmannsthal (born c. 1935), who married Roderick McEwen. Raimund later married Lady Elizabeth Paget.
From 1936–1937, she had an affair with English choreographer Sir Frederick Ashton, his homosexuality notwithstanding. After the affair ended, her love for him continued, though she had two subsequent marriages, both to gay Englishmen.
After divorcing Raimund in 1939, she married Philip John Ryves Harding, a journalist. The wedding took place on March 27, 1940, in Faversham, England. Out of this union, one daughter, Emily Edwina Harding, was born in 1942.
Lastly, she married David Pleydell-Bouverie (born April 20, 1911, the grandson of William Pleydell-Bouverie, 5th Earl of Radnor) on May 12, 1946 in Reading, Vermont. The couple resided in New York City and Glen Ellen, California, before divorcing in 1952.
Ava Astor died of a stroke in her East Sixty-First Street apartment on July 19, 1956, aged 54. She was a patron of the arts, including the ballet companies of London and New York City.
Her will was admitted to probate on November 5, 1956, in Manhattan Surrogate Court. Her assets, totaling $5,305,000, were divided among her four children.