Sybe Klazes Kooystra, born in Grouw circa 1792, son of Klaas Johannes Kooystra (worker) and Hiltje Johannes, barge hand and bargeman.

Sybe was married in Idaarderadeel on March 17, 1817, at the age of approximately 25 to
Antje Uiltjes Veenema (aged 23 years), born in Wartena on January 29, 1794, christened there on February 23, 1794, daughter of Uiltje Hoytes Veenema (peat cutting supervisor) and Feikjen Wybes Feenstra, living in Grouw, died in Lemsterland on August 29, 1863, aged 69 years.

• 1 : Klaas Sybes Kooystra, born in Wartena on February 11, 1817.
  Klaas was married in Idaarderadeel on September 5, 1845, at the age of 28 to Aaltje Jans Gorter (aged approximately 22 years), born in Grouw circa 1823, daughter of Jan Taekes Gorter and Sibbeltje Durks Grouw.
  

• 2 : Uiltje Sybes Kooystra, born in Idaarderadeel on February 27, 1819.
  

• 3 : Hoyte Sybes Kooystra, born in Idaarderadeel on June 29, 1824.
  

• 4 : Feikjen Sybes Kooistra, born in Lemmer on October 7, 1826.
  

• 5 : Johannes Siebes Kooystra, born in Lemmer on August 20, 1828.
  

• 6 : Geertje Siebes Kooistra, born in Lemmer on October 8, 1832.
  

• 7 : Geertje Siebes Kooystra, born in Lemsterland on May 3, 1834.