Marylou Whitney, who fled Kansas for New York with dreams of being an actress and found instead a life of immense wealth and privilege, marrying into two of America’s richest families and reigning for decades as the social queen of the Saratoga and Lexington racing seasons, died on Friday July 19 2019 at her home in Saratoga Springs, N.Y. She was 93. Mrs. Whitney, the widow of Cornelius Vanderbilt Whitney — businessman, film producer, philanthropist, horse breeder, polo player — was a tireless society hostess, a patron of the arts and the author. She was a sportswoman and a thoroughbred breeder, inducted this year into the National Museum of Racing and Hall of Fame in Saratoga Springs. In Lexington Kentucky, Mrs. Whitney took a passionate interest in the C. V. Whitney Racing Stable, whose great thoroughbreds in its trademark Eton blue and brown included Equipoise, Phalanx and Counterpoint. The stables later ceased operations, and Mr. Whitney died in 1992 at age 93, but Mrs. Whitney carried on the tradition, establishing her own stables. She was born Marie Louise Schroeder in Kansas City, Mo., on Dec. 24, 1925, to Harry and Marie Jean Schroeder. She attended Southwest High School and enrolled at the University of Iowa but had to return home at 19 when her father, a bank officer as well as an accountant, died. She found work at a Kansas City radio station as a wartime disc jockey, and then she took off for New York with dreams of acting. She married Frank Hosford of the John Deere farm machinery family. They had four children. The family later moved to Phoenix, where she earned a real estate license and worked part time as the hostess of a television cooking show. After divorcing their spouses, she and Sonny Whitney married in 1958 at a ranch in Carson City, Nev. She was the fourth wife of Sonny Whitney, whose mother was Gertrude Vanderbilt Whitney, the artist who founded the Whitney Museum of American Art in New York. On his death Mr. Whitney left his entire fortune of $100 million (the equivalent of about $179 million today) to his wife. It had grown from a $20 million inheritance from his father, Harry Payne Whitney, thanks to shrewd investments in Pan American Airways, which the younger Mr. Whitney helped found; in movies like “Gone With The Wind,” in which he had a major financial interest; and in Marineland, the Florida tourist attraction, which he had built. She met John Hendrickson, a former aide to Gov. Walter J. Hickel of Alaska and married in 1997; she was 71 and he was 32. She named Mr. Hendrickson vice president of Whitney Industries, which manages the family’s lumber business and land holdings. Mrs. Whitney’s survivors include Mr. Hendrickson and five children, Mary Louise, Frank, Henry and Heather Hosford and Cornelia Vanderbilt Whitney, her only child from her marriage to Mr. Whitney.