Your email is very interesting to me, especially your comment concerning that you had seen indications that William Donnelly was a son of Olive's sister. I have tons of Coffin data which I believe is much of your research. I sent to the Special Collections Office, University of Nevada, Reno, Library. They sent me a large packet of information and photos. Also, I have a good collection of the census on the Coffin family. In 1910 I found a Supplemental Census that was an Infants Shelter in San Francisco that had Allein Donly and Ralph Donely as Wards (note: the spelling of names was incorrect)- Ralph was one year and Allein was 3. I remember at the time I found it I had a "heart tug" to see the children there at such a young age.
Who was Norman? Was he a third child of Mabel?
Well, I don't have anything on William Donnelly except what I found on the 1910 Virginia City census. He was enumerated as William T, a. 31, b. Idaho and father b. Minnesota and Mother Nebraska.
You can email me directly if you would like. You have sparked my research bug and I will attempt to look for William Donnelly and perhaps we can find out what happened to him.I am most interested in his parents.