Despite the comparisons, Godowsky had her moments. She was an accomplished dancer who toured aged 11 in a children's musical, Daintyland, and never let George and Ira forget that, in the days when the brothers were grateful for $15 paychecks from Tin Pan Alley, she was the family's main breadwinner.
In the late 1920s, she sang in a couple of Broadway shows, but, by the time the family moved into the house on West 103rd Street in Manhattan made famous in the film Rhapsody in Blue, Frances seemed resigned to tailoring her career to fit in with that of her older brothers.
She would often be summoned to George's room on the fifth floor and enlisted to sing the Gershwin compositions that would later be Broadway hits. Although she possessed a small voice by the standards of the day, George, who loved her interpretations of his sometimes complicated music and the way she kept the rhythm going, made her his personal chanteuse, and the two entertained at parties in New York.
In early 1928, George brought her along on a European trip to escape a boring doctor she was dating. By the time she returned six months later, she had so wowed Cole Porter at a party in Paris that he designed a show for her at the famous Les Ambassadeurs nightclub where she sang Gershwin tunes with George as her accompanist.
Although the engagement drew professional offers, she returned to New York where she had a new suitor, one of George's poker cronies, Leopold Godowsky Jnr, the son of the celebrated Austrian pianist. They married in 1930 and settled in Rochester, New York, where Leopold helped invent Kodachrome, the revolutionary slide film. Godowsky played a similar role for her husband as she had for her brothers and would pose in a bright red beret and bottle-green dress as a photographic test model.
After George Gershwin's death in 1937, the couple moved to Westport, Connecticut. It was there that Frances Godowsky, who had begun sculpting in Rochester, took up painting and turned out hundreds of oils and acrylics. This accomplishment helped soften the blow for her when the film Rhapsody in Blue came out in 1945 and excised her and her third brother Arthur from the Gershwin family.
Frances Gershwin was born on the Lower East Side of Manhattan on Boxing Day 1906, exactly 10 years the junior of her eldest brother, Ira. The Gershwins had a peripatetic childhood as their father, Morris, repeatedly moved the family to be near his latest job. Ira once calculated that between 1900 and 1917 the family lived in 28 different apartments, 25 in Manhattan and three in Brooklyn.
Although painting remained her main artistic concern, Godowsky re-emerged as a singer in her later years. Her 1975 album, Frances Sings for George and Ira, won acclaim and, after a granddaughter suggested she have vocal training, she began a long-deferred professional career, singing Gershwin tunes at the Lambs Club in Manhattan until two years ago. Her husband and her brother Ira both died in 1983.
Frances Gershwin, artist and singer: born New York 26 December 1906; married 1930 Leopold Godowsky Jnr (died 1983; one son, three daughters); died New York 18 January 1999.