As far as known, Maurice's mother visited the address Meent 85 in Rotterdam where her son lived. She lived up from 27 June 1936 at Nieuwe Binnenweg 324c. Maurice's wife and one of the children survived the bombardment of Rotterdam and could leave Holland for Argentina in 1941.
Mother Hermine Fischer, son Maurice Joost Son and daughter Anita Jos were found dead on 22 May 1940 at Meent 85 in Rotterdam and were buried that same day in a common grave at Crooswijk