His parents were:
Daniël Pront (1867-1943)* and
Kaatje Pront-Lopes Dias (1864-1943)*
His brothers and sisters were:
Saartje Pront (1887-1888)
Aäron Pront (1888-1942)*
Sara Bromet-Pront (1890-1943)*
Alexander Pront (1892-1944)*
Marianne Sigaar-Pront (1894-1943)*
Judith Samson-Pront (1902-1943)*
(* ) persons with a file on this site
source for the family links:
Schenk & Pruijt/Preuij - Genealogy
http://www.schenk.nl/genealogie/
http://gw.geneanet.org/schenk?lang=en&p=leendert&n=pront