(1) He is married to Oelka - Oelke Fokkema.
They got married on July 4, 1936 at Emmen, Gemeente Emmen, Drenthe, Nederland, he was 22 years old.Source 4
(2) He has/had a relationship with Hendrikje Koekoek.
grandparents
parents
brothers/sisters
children
Johan Gerard - Johan Gerhard Santen | ||||||||||||||||||
(1) 1936 | ||||||||||||||||||
Oelka - Oelke Fokkema | ||||||||||||||||||
(2) | ||||||||||||||||||
Hendrikje Koekoek | ||||||||||||||||||

Pauline Berens: Genealogienetwerk zus Greetje Berens voorheen EemslandBoekweitBoerenImmigratie
https://www.genealogieonline.nl/the-dutch-connection/I22042.php