Family #26 in the 1767 Stephan census.
Anna Catharina Stürtz Usinger is first mentioned with her family in the Kulberg Reports as the 16-year-old daughter of Johann and Catharina Stuertz. 
One year later, at the time of the 1767 Stephan census, her name is no longer listed with the rest of her family. She would have been 17 years old, and possibly married. Here is the listing for her family, without her name included.
1767 Stephan Census, without Anna Katharina 
After searching the Stephan census for any Anna Catharinas who were 17 years old, I found only one: Anna Katharina Usinger.  She was married to Andreas Usinger, 21, a farmer from Reichenbach, Germany.  Those villages weren't particularly close,  so the couple probably met on the journey from Oranienbaum to the Volga River region and married shortly after their arrival. At the time of the 1767 census, the couple had no children. 
1767 Stephan Census, with Anna Katharina in Usinger Family
There are no Usingers in Stephan in the 1798 census.  The only village where any Usingers appear is Müller, and Andreas Usinger is not one of them.  That said, however, a closer examination of the 1798 Müller Census reveals that the Usingers in that village were Andreas Usinger's sons. His widow's name in that census, however, is Anna Christina Müller, not Anna Katharina Stürtz. This indicates that Anna Katharina Stürtz Usinger passed away in Stephan some years earlier.
The Usinger children are listed in three different households in the 1798 Müller census: three brothers in family #Ml105, a brother and sister in family #Ml12 with their stepmother and stepfather, and one brother in #Ml27.  The siblings are, in order of age:
Johannes and Johann Heinrich appear to be twins, or possibly born just a year apart, one at the beginning of 1775 and one at the end of 1775. The largest gap between ages is between Johann Georg, born in 1780, and Johann Christian, born in 1785. It's possible that Anna Catharina Stürtz Usinger passed away during that time and her widower Andreas remarried Anna Christina Müller by 1784. That would make second wife Anna Christina the mother of Andreas' youngest child, Johann Christian. Andreas died by 1788, allowing her to marry her second husband Johann Heinrich Bacher, 31, also originally from Stephan, by 1788. Anna Christina and Johann Heinrich Bacher had two children of their own, the first of whom was born in 1789.
I don't have a copy of the 1775 Müller census, which would be helpful in determining if Anna Catharina Stürtz Usinger was still alive at that time. That would confirm (or not) if she was the mother of Andreas' three oldest children. The mother(s) of the two younger children is just a guess, but somewhat educated, based on what the information provided in the 1798 Müller census.
If someone has a copy of the 1775 Müller census and would like to share that information, it would be a great help in determining who the mother(s) of Andreas' children were. Feel free to update this profile directly, or contact me with the details and I will make any necessary changes to the profiles.
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