Willem Heinsius, born circa 1815 (?), shopkeeper.

Willem was married to
Minke Tjeerdes, born circa 1819 (?).

• 1 : Dubbeld Heinsius, born in Enkhuizen circa 1842.
  Dubbeld was married in Workum on April 26, 1863, at the age of approximately 21 to Gelske Johannes Feenstra (aged 21 years), born in Eernewoude on January 10, 1842, daughter of Johannes Baukes Feenstra (peat cutting supervisor, barge hand, bargeman, eel bargeman, barge hand and eel bargeman) and Antje Gjalts Wester, died before August 23, 1907, aged at most 65 years.