Jan Mook, born circa 1849 (?), shoemaker.

Jan was married to
Aaltje Renzema, born circa 1853 (?).

• 1 : Trijntje Mook, born in Anjum on February 5, 1876, died in Leeuwarden on April 12, 1920, aged 44 years.
  Trijntje was married in Leeuwarden on April 2, 1902, at the age of 26 to Klaas Baukes Feenstra (aged 29 years), born in Oosterlittens on August 18, 1872, son of Bauke Ottes Feenstra (journeyman baker and baker) and Grietje Jacobs Piersma, journeyman baker, died in Leeuwarden on August 13, 1926, aged 53 years.
  Klaas was married afterwards in Leeuwarden on November 12, 1921, at the age of 49 to Sjoukje van der Meer (aged 31 years), born in Grouw on October 12, 1890, daughter of Klaas van der Meer (blacksmith) and Froukje Gorter.