"United States Census, 1880," database with images, FamilySearch (https://www.familysearch.org/ark:/61903/1:1:MXVY-RF1 : 12 November 2020), Dorothea Otting in household of Christian Otting, Monroe, Illinois, United States; citing enumeration district ED 70, sheet 138D, NARA microfilm publication T9 (Washington, D.C.: National Archives and Records Administration, n.d.), FHL microfilm 1,254,237.
The newspaper, Montgomery City Standard from Montgomery, Missouri apparently had an obituary for Mrs. Dora Oetting age 72 who died 3 Nov 1905. Ancestry.com connects this with the findagrave memorial for Dorotheeth C. Oetting. (It also connects her with Dietrich Oetting that married Kohlmeier) Perhaps newspaper article will help with maiden name.
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