Heinrich Willumsen and Maria Schenk were born probably around the 1860'es, and married about 1885. The got at least a son, Georg Diedrich Willumsen (1888-19??). He moved to Denmark in 1908 from Altona at Hamburg, and married in 1911 Kaja Bergthora Julie Gade (1890-1975). He got Danish citizenship when they 1912 got a son, Kaj Aage Willumsen (1912-1992). 6 years later they also got a daughter, Harriet (1918-1996).

Kaj Aage Willumsen married in 1933 Helga Marie Bendix (1912-).
They got 2 children, Hanne (1940-2006) and Ole (1943-) (Yes, thats me, in fact).