She'd married Charles Otremba, according to the write-up, but I had no idea who he was other than "Otrembas are related." So, we just saved it, knowing we'd eventually find the connection.
It turns out that Charles was also known as Karl, and they left Minnesota in 1906...no wonder I have no family references to them. Karl was the son of Johann Otremba and Anna Rosina.
Anyway, last night, Larry searched ancestry.com for Mary Jendro and there she was, with pictures, and how they fit in the family.
A photo of Mary and Charles in 1942, and a newspaper article about their daughter as an old woman adds to bits and pieces we've found online:
The photo of John and Rose Otremba (added June 2010) is from a Morrison County Farm Directory in the 1980s. He was Karl & Mary's son.