Isaac married Doris Marion Sweetapple on 29 Dec 1915 in Wellsburg, Brooke, West Virginia. Doris (daughter of Albert Lewis Sweetapple and Lucy Katherine Russell) was born on 19 Sep 1895 in Brush Hill, Venango, Pennsylvania; died on 14 Sep 1996 in Sligo, Clarion, Pennsylvania; was buried in Clintonville, Venango, Pennsylvania. [Group Sheet]

1. Erma Louise Hoffman was born on 29 Sep 1916 in Clintonville, Venango, Pennsylvania; died on 12 Apr 1997 in Clintonville, Venango, Pennsylvania.
2. Harry Albert Hoffman was born in 1918 in Pennsylvania; died in 1921 in Pennsylvania; was buried in Clintonville, Venango, Pennsylvania.
3. Evelyn F Hoffman was born on 6 Mar 1925 in Clintonville, Venango, Pennsylvania; died on 14 Oct 2015 in Clarion, Clarion, Pennsylvania; was buried on 19 Oct 2015 in Clintonville, Venango, Pennsylvania.