Kay Thompson, born Catherine Louise Fink on November 9, 1909, in St. Louis, Missouri, was a multifaceted American entertainer renowned for her work as an author, singer, vocal arranger, composer, musician, dancer, actress, and choreographer. She was the second of four children born to Leo George Fink, a Jewish Austrian-born pawnbroker and jeweler, and Harriet Adelaide "Hattie" Tetrick, a Christian.

Thompson's career began in the 1930s as a singer and choral director for radio, gaining prominence through shows like "Bing Crosby Entertains" and "The Fred Waring-Ford Dealers Show." She married trombonist Jack Jenney in 1937, though the marriage ended in divorce in 1939. Her radio work led to her motion-picture debut in "Manhattan Merry-Go-Round" (1937).

In the early 1940s, Thompson joined MGM as a vocal arranger and coach, working on musicals such as "Ziegfeld Follies" and "The Pirate." She coached stars like Judy Garland and Frank Sinatra. Thompson's film acting career peaked with her role as fashion editor Maggie Prescott in "Funny Face" (1957).

Thompson also gained fame for her nightclub act, "Kay Thompson and the Williams Brothers," and authored the beloved "Eloise" children's book series, collaborating with illustrator Hilary Knight. Her books, including "Eloise in Paris" and "Eloise at Christmastime," became best-sellers.

Thompson married screenwriter William Spier in 1942, but the marriage ended in 1947. She passed away on July 2, 1998, in New York City, leaving behind a legacy celebrated with a plaque on the St. Louis Walk of Fame.