In the Amsterdam city data archives (http://stadsarchief.amsterdam.nl/) we found difficult to read copies of data ( 0riginals were lost) which gave already some clues about the family. Also they raise more questions about the family.
Our main interest regarding the family is to find the (story of the) older brother of HJH Hartog.
From the attached PDF documents of HJH Hartog his parents "family card" we found out about the older brother.
And after that we found the brother his own " family card".
Till today we can not find much more about his brother. We hope he survived WWII due to changing his identity and/or moved/feld abroad.
All we know (if read correct from both cards) is:
HJH Hartog his brother his forename is:
Lodewijk Benedictus Daniel (LBD)
His date of birth is :2 april 1901
City of birth: Berlin, Germany
Nationality: Dutch
Proffesion: Clerk (kantoorbediende)
Their father Hendrik was an agent (Handelsagent) and on this and other found data it shows that the family moved several times within Europe. For example to London, Warsaw, Magendburg, Berlin.
LBD Hartog last info is that he moved to Paris (in 1923?).
Hope you can help with info about this family, the brother. Also very welcome information on how to continue this search.