William married Ethel Minnie Bowen on 25 Dec 1899 in Shell Rock, Butler, Iowa, USA. Ethel (daughter of Byron Bowen and Jerusha Minnie Gibson) was born on 9 Mar 1880 in Shell Rock, Butler, Iowa, USA; died on 4 Jun 1967 in Waverly, Bremer, Iowa, USA. [Group Sheet] [Family Chart]

1. Glo May Simpson was born in 1900.
2. Eva Simpson was born on 11 Apr 1902 in Jackson Township, Bremer, Iowa, USA; died on 20 Sep 1996 in Riverside, California, USA.
3. Leah Mayme Simpson was born in 1903 in Janesville, Bremer, Iowa, USA; died in 1963.
4. Ruth Simpson was born in 1905; died in 1905.
5. Bernice LaClaire Simpson was born in 1907; died in 2013.
6. John William Simpson was born on 2 Jan 1910 in Jackson Township, Bremer, Iowa, USA; died on 4 Apr 1990.
7. Stanley Byron Simpson was born on 15 Nov 1912 in Bremer, Iowa, USA; died on 29 Dec 1986.