Friedrich Heinrich was born in 1856. He is the son of Heinrich Ahrens and Theresia Multhaup.
"Deutschland Geburten und Taufen, 1558-1898," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:NZ59-DDQ : 28 November 2014), Friedrich Heinrich Ahrens, 05 Jun 1856; citing ; FHL microfilm 1,050,742.
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