Gerrit Jan ter Plegt, born circa 1851 (?), gemeente secretaris te Warmenhuizen (1908).

Gerrit was married to
Neeltje Holterman, born circa 1855 (?), died before 1908, aged at most 53 years.

• 1 : Petrus Jacobus ter Plegt, born in Warmenhuizen on January 14, 1878, landmeter bij het kadaster, died after 1949, aged at least 71 years.
  Petrus was married on August 26, 1908, at the age of 30 to Jetje Catharina Reinouts van Haga (aged 20 years), born in Sneek on March 4, 1888, daughter of Petrus Reinouts van Haga (tobacco manufacturer and tabakskerver (1888)) and Catrina Joanna Bangma, died between 1926 and 1949, aged 38 years to 61 years.