My understanding is that the early children of Christian and Rosanna were born in Germany (I guess Wurtemberg), and the later ones in the US, in Ohio, Michigan, or Indiana. The order of the children is: Rosa, Lucy, Frank, William, Ernest, Edward. I know Ed was born in the US.
Ira Ford Lewis Publishing Company, 1920 - De Kalb County (Ind.) pg. 265
"United States Census, 1900," database with images, FamilySearch(https://familysearch.org/ark:/61903/1:1:MM1V-B9J : 20 January 2015), Christian G Wolf in household of Rosa C Wolf, Lima Township (incl. Howe Military School), LaGrange, Indiana, United States; citing sheet 9A, family 199, NARA microfilm publication T623 (Washington, D.C.: National Archives and Records Administration, n.d.); FHL microfilm 1,240,383.
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