Jacob Müller was born 31 May 1733 in Sprendlingen, Pfalz. His wife, Susanna Elz, was born 4 Nov 1728 in Sprendlingen, Pfalz. They married on 28 Sep 1755. They had four children in Sprendlingen before immigrating to Russia: Johann Bernhard, Anna Margareta, Johann Wilhelm, and Anna Gertruda. Anna Gertruda died during the trip through Russia.
- Parish records of Sprendlingen, Dekanat Wöllstein, Central Archive of the Evangelical Church in Hessen and Nassau (Archion.de)