Anna Capeller was born in 1853 at Kempten, Bavaria. She married Viktor Hilgard (1841-1899), an engineer and an uncle of Henry Villard (born Hilgard). The couple lived in Regensburg and had four children together, the eldest born in 1876 and the youngest in 1885. Viktor Hilgard died in 1899; Anna Capeller Hilgard died in 1926.

Source: Gertrud Baecker and Fritz Engelmann, Die Kurpfälzischen Familien Engelmann und Hilgard (Ludwigshafen am Rhein: Richard Louis Verlag, 1958)