This is Carol Grace Matthau, Capote's friend and the basis for Holly Golightly (although he also said he included traces of dancer Joan McCracken and Marilyn Monroe).
A Celebrated Original
The Original Holly Golightly – The New York Times
Carol Grace (September 11, 1924 – July 20, 2003) was born in the Lower East Side of Manhattan to the sixteen-year-old daughter of Russian-Jewish immigrants, and an unknown father. Later, her mother Rosheen Marcus identified him as British actor Leslie Howard, from “Gone with the Wind”. She was eventually placed in foster care until the age of eight when her mother married Charles Marcus, the head of the Bendix Aviation Corp., whose name she took.
Young Carol attended the Dalton School during high-school. It was around this time she met her life-long friends Oona O’Neill (daughter of Eugene O’Neill) and heiress Gloria_Vanderbilt. She was also pals with young Truman Capote, whom she met when both were thirteen. Carol’s personality, not occupation, was the inspiration for Capote’s character Holly Golightly, the heroine of his 1958 novella “Breakfast at Tiffany’s”.
Carol twice married and divorced Pulitzer-Prize winning writer William Saroyan, with whom she had two children, Aram Saroyan, a writer,