Theodore Regensteiner (born May 17, 1868, in Munich, Germany, to Albert (Abraham) (?-1904 in Pasing) from Pflaumloch and his first wife Fannie, née Heymann. He had an older brother Siegfried (1866-1927) founder of the Automobilwerk Pasing near Munich. Theodore lost his mother age 3 and his stepmother Bertha, mother of Martin (?-1909 in Chicago) and Otto (1877-1941 in Kaunas) became a determining factor in bringing about his emigration in 1884 (he was age 15) to the USA.
Theodore Regensteiner, born on May 17, 1868, in Munich, Germany, to Albert and Fannie Heymann, had an older brother named Siegfried who founded Automobilwerk Pasing near Munich.  He lost his mother at age three and his stepmother, Bertha, became a significant influence in his emigration to the USA in 1884 when he was fifteen years old.