Seth married Abigail Margaret Hall in 1888 in Valeria, Iowa. Abigail (daughter of William Hastings Hall and Elizabeth McQuiston) was born on 18 Aug 1871 in Valeria, Iowa; died on 19 Jul 1919 in Pendleton, Umatilla County, Oregon. [Group Sheet] [Family Chart]

1. Eva Charlotte Richardson was born on 13 Oct 1889 in Pendleton, Umatilla County, Oregon; died on 30 Jun 1971.
2. Emma Lillian Richardson was born on 7 Jan 1893 in Pendleton, Umatilla County, Oregon; died in Jun 1976 in Weston, Umatilla County, Oregon.
3. Edith Mae Richardson was born on 12 Nov 1897 in Pendleton, Umatilla County, Oregon; died in Sep 1970.
4. Edward Hastings Richardson was born on 10 Oct 1900.
5. Esther Philena Richardson was born on 30 Jan 1903.
6. Elizabeth Alice Richardson was born on 2 Jul 1906 in Pendleton, Umatilla County, Oregon; died on 29 Mar 1915 in Pendleton, Umatilla County, Oregon.