Question: Who founded an American family notable for their social prominence, wealth, business enterprises and philanthropy, who has a member by marriage who isan American poet, writer, racehorse owner/breeder, socialite, and philanthropist ?  

Context paragraphs:
Salusbury family: The Salusbury family is an Anglo-Welsh family notable for their social prominence, wealth, literary contributions and philanthropy.

Alphonse James de Rothschild: Mayer Alphonse James Rothschild (1 February 1827 – 26 May 1905), was a French financier, vineyard owner, art collector, philanthropist, racehorse owner/breeder and a member of the prominent Rothschild banking family of France.

Helen Hay Whitney: Helen Julia Hay Whitney (March 11, 1875 – September 24, 1944) was an American poet, writer, racehorse owner/breeder, socialite, and philanthropist.  She was a member by marriage of the prominent Whitney family of New York.

Madeleine A. Pickens: Madeleine Anne Pickens is a business woman and philanthropist who has lived in the United States since 1969.  She is a developer of and stockholder in the Del Mar Country Club in Rancho Santa Fe, California, and the owner of the Mustang Monument: Wild Horse Eco-Resort near Wells, Nevada and the founder of Saving America's Mustangs.  She is also a thoroughbred racehorse owner and breeder.  She is the widow of American businessman Allen E. Paulson and former wife of billionaire T. Boone Pickens.

Gertrude T. Widener: Gertrude T. Douglas Widener (July 8, 1897 - February 3, 1970) was an American socialite and a successful Thoroughbred racehorse owner and breeder.  Born in Albany, New York, she was the daughter of New York State Senator, Curtis N. Douglas.

Jasmine (family): The Jasmine family is an American family notable for its entrepreneurial endeavors in the U.S. Northeast.  The family garnered modest prominence through its business as the major distributor of fresh produce in Reconstruction era New York City.  Until the 1920s, the Jasmine food goods trade became an innovator in using the railroads to carry produce, preserved foods, and wine from California to markets and vendors in the New York tri-state area.  Most early Jasmine family interests were sold and incorporated into the Great Atlantic and Pacific Tea Company in 1899, allowing that company to vastly expand its holdings and stores in the New York metropolitan area.  Since the 1920s, the Jasmine family has been involved in philanthropy, including support for Catholic schools and education.

Thomas Mellon Evans: Thomas Mellon Evans (September 8, 1910 – July 17, 1997) was a financier who was one of the early corporate raiders in American business as well as a philanthropist and a prominent Thoroughbred racehorse owner and breeder who won the 1981 Kentucky Derby and Preakness Stakes.

Muriel Vanderbilt: Muriel Vanderbilt (November 23, 1900 – February 3, 1972) was an American socialite and a thoroughbred racehorse owner/breeder who was a member of the wealthy Vanderbilt family.

Whitney family: The Whitney family is an American family notable for their social prominence, wealth, business enterprises and philanthropy, founded by John Whitney (1592–1673) who came from London, England to Watertown, Massachusetts in 1635.  The historic family mansion in Watertown, known as The Elms, was built in 1710.

Louis Freedman: Louis Freedman CBE (1917–1998) was a British businessman and racehorse owner and breeder.  He was chairman of Land Securities from 1957 to 1977 and in horse racing he was the owner and breeder of a number of top-class racehorses, most notably the 1987 Epsom Derby and St Leger Stakes winner Reference Point.

Supporting paragraphs: Helen Hay Whitney Whitney family
Answer: John Whitney