I am George's grandson. He married Elaine and had three children: Joan (my mother, deceased 2002), Stanley (who died as a child), and Tom. Stanley Taffel (1901) at least one son, Ron Dean, who lived in Manhattan and had a landscaping business. Here is a link on the family's connection with the Gershwins:
http://www.7x7.com/arts/sf-opera-porgy-bess