He immigrated to Missouri, arriving in the United States on September 1, 1885. He became a citizen on March 15, 1898 when he and his family lived on a farm near Red Wing, Minnesota, thus conferring citizenship on his wife as well. Wilhelm and Anna had twelve children, of whom Agnes was the tenth.

In Germany the family’s last name was Siepen-Sothmann. In 1887 Anna and her twin sister Maria (Eickhoff), her sister Franciska (Ebsch), and brother Theodore immigrated to Sarcoxie, Missouri where their sister Elizabeth (Graskemper) had settled in 1882. Anna’s first cousin Elizabeth Muetel married August Gaertner, older brother of Wilhelm, by 1888. Wilhelm moved to Cleveland as did Anna and the two were married in 1889.