I don't know if you'll see this since your message is quite old. I ran across it while searching the Waushara County site. Were your Frank and Mary Nelson Danish? If so, I may have information. I believe that Frank is perhaps Frank C. Nelson, brother of my great-grandfather. If you see this, respond and let me know if they were Danish. I believe that they are the same family, and if so, I have a lot of information on the Nelson family, both in Wisconsin and in Denmark.