Forsythe was married three times. He married Parker McCormick in 1939. They divorced in 1943. He married Julie Warren in 1943. She died in 1994 when Forsythe decided to turn her off of life support when she had breathing problems. He married Nicole Carter in 2003. They were married until his death in 2010. Forsythe had a son, two daughters, six grandchildren, and four great-grandchildren.