Maria Friedrika was born in 1840. She is the daughter of Theresia Multhaup.
Maria was born 5 years before her mother married Heinrich Ahrens.
"Deutschland Geburten und Taufen, 1558-1898," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:NVHC-M5F : 28 November 2014), Maria Friedrika Ahrens, 15 Jan 1840; citing ; FHL microfilm 1,056,023.
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