Richard Parkinson Sedgwick [John Sidgwick / Alice Wilkinson]
Jessie Miriam Williamson [D H Williamson, Jessie Unknown]
Cynthia May Willey [Levi Willey / Mary Lucenda Washburn]2
At the 1910 census, Richard was widowed and living with his parents, and reported as widowed, but his estranged wife Miriam and a son were living not far away with her parents.
A family tree exists at Ancestry.com which shows one Cynthia Maye Willey b. February 16, 1887 who married Unknown Sedgwick to be the daughter of Levi Willey (1855 - 1916) and Mary Lucenda Washburn (1861 - 1925), both born Iowa. I subsequently found her with them in the 1900 census, linked above.
There is no indication that Cynthia May Willey was married before Richard, so based on the 1911-1912 birth of daughter Dorothy M, I assume that Richard and Cynthia were married in late 1910 or early 1911.
Children of Richard Parkinson Sedgwick and Jessie Miriam Williamson:
b. abt 1908, [Grover, Weld,] Colorado2
Children of Richard Parkinson Sedgwick and Cynthia May Willey:
Dorothy M Sedgwick
b. abt 1911, Colorado2
Marjorie G Sedgwick
b. abt 1917, Colorado2
Delpheus Richard Sedgwick
b. November 14, 1921, Newcastle, Weston, Wyoming2,4
d. January 5, 2005, Multnomah County, Oregon5
1. Records of descendant/researcher of this family:
2. Census records, any of those indicated.
3. Descendants of Anthony and Alice (Sayer) Wilkinson
4. Iowa, World War II Bonus Case Files, 1947-1954
5. Oregon, Death Index, 1898-2008