Robert S. Isenstein “Bob”, 81, died Oct. 21 at his home in Riderwood Village from prostate cancer. He is survived by his wife, Margaret; and his sons, Mark and Neal, his wife Anna Tucker. Service and interment will be private. His family is hosting a memorial luncheon Dec. 13 at 12:30 p.m. at Riderwood Village Town Center, 3140 Gracefield Rd. in Silver Spring, where friends and colleagues are invited to come and to share their memories of Bob. Please call 301-328-0844 by Nov. 26 to make your reservation. Memorial contributions may be made to the Hebrew Home of Greater Washington, 6121 Montrose Rd., Rockville, MD 20852 or the Jewish Federation of Greater Washington, 6101 Montrose Rd., Rockville, MD 20852.