Franz Wilhelm was born in 1839.
"Deutschland Geburten und Taufen, 1558-1898," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:NVS3-FYF : 28 November 2014), Franz Wilhelm Ahrens, 25 May 1839; citing ; FHL microfilm 1,050,742.
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