Østein married Gjertrude Henriksdatter Mugaas about 1893. Gjertrude (daughter of Henrik Nilsson Mugås and Marta Gulleiksdatter) was born on 3 Nov 1866 in Voss, Hordaland, Norway; died on 1 May 1923 in Robsart, Saskatchewan, Canada. [Group Sheet] [Family Chart]

1. Gudve Thormoseth was born about Sep 1889 in Norway.
2. Olina M Thormoseth was born in Nov 1893 in Wisconsin, USA.
3. Martha L Thormoseth was born on 20 Jun 1895 in Wisconsin, USA; died on 31 Aug 1903 in Sumner, Barron County, Wisconsin, USA; was buried in Sumner, Barron County, Wisconsin, USA.
4. Einart Albert Thormoset was born on 11 Aug 1897 in Canton, Buffalo County, Wisconsin, USA; died in 1982; was buried in Maple Creek, Saskatchewan, Canada.
5. Gertie Regina Thormoset was born on 24 Dec 1899 in Barron County, Wisconsin, USA; died on 25 Dec 1981 in Maple Creek, Saskatchewan, Canada.
6. Henry Thormoset was born about 1902 in Wisconsin, USA.