Well, this doesn't really answer your overall question, but I found it very interesting because there are many Hemauers in my family!
I found Katherine Hemauer and Frank Xavier Joas, both born in Germany, married in 1870, living in Stockbridge and having 5 children: Joseph G (1869), George (1871), Mary (1876), Anna (1879), and Rose (1887). What was interesting to me was that I had no Katherine Hemauer in my tree, but I found her parents to be George and Crescentia Leichtinger which are my ggggrandparents!
This I got off the Marchant family tree. Not sure how much you know about Frank Joas, but his parents are Joseph Joas (1803-1878) and Josepha Bach (1811-1865). The tree lists Joseph's second wife as Margaretha Blank, but no further children. The family came from Schopflohe, Bayern, Germany. Here are Joseph and Josepha's other children:
Joseph (1836-1883) married Maria Lehner and Mary Schue
Anna Maria (1839-1914) married Balthasar Theis
George (1849-1916) married Mary Hemauer (!)
Maria Magdalena and another Frank died in infancy.
George and Mary also lived in Stockbridge. Hope that helps!