He is married to Kaatje Lourens.
They got married on October 13, 1927 at Dantumadeel, Friesland, Nederland, he was 23 years old.Source 3
grandparents
parents
brothers/sisters
children
Folkert de Graaf | ||||||||||||||||||
1927 | ||||||||||||||||||
Kaatje Lourens | ||||||||||||||||||
Geboorteregister 1904, Kollumerland c.a.
https://www.graftombe.nl/names/info/195325/graaf_de
Huwelijksregister 1927, Dantumadeel