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 ?  
Sentence (from "Helen Hay Whitney"): Helen Julia Hay Whitney (March 11, 1875 – September 24, 1944) was an American poet, writer, racehorse owner/breeder, socialite, and philanthropist.
Relevant evidence: No