Brick Wall #2 Sweden and Minnesota

There will be a flurry of blogposts today in preparation for tomorrow's Brick Wall meeting.  Please join me in thinking about how we can help.  

Rich L. asks:

Here is my brick wall.  My grandmother, Elsie Stella Nilson Olson, was adopted.  We don't know exactly who her biological father is.  Elsie's mother was Margreta (Maggie) Frisk, b. 9 Apr 1859 in Sladaborg, Orsa, Dalama, Sweden and d. 26 May 1929 in Cass, Minnesota.  We think she married Austrian born Peter "Nils" Nilson or Nillson or Nielson on 22 Sept 1882? in Minnesota.  Elsie was born 24 Apr 1882 in Isanti, Isanti County, Minnesota and died 21 Aug 1957 in Puyallup, Pierce County, WA.

 The story I remember is that Maggie Fisk married Peter Nils Nilson.  He went off on a job and never returned with no word what happened to Nils.  When Elsie was about 4 years old her mother Maggie married Peter E. Olson, born Jan 1859 in Sweden.  Peter adopted Elsie and gave his name Olson.  Peter was a super nice Dad and treated Elsie as his own child.  I met most of Elsie's step brothers and sisters from Minnesota when I was a kid. 

Rich tested his DNA so this may help.