Alexander van Gelder

Alexander van Gelder was a son of Lion Louis van Gelder and Eva van Messel.
He went into hiding with a friend for two years in Voorburg between 1942 and 1944. He was arrested after betrayal. After a stay in the hospital because of an attempt to take his own life he was deported to Westerbork.
Addition of a visitor of the website

The Sutthoff database says Alexander van Gelder died there 6 Dec 1944

https://www.ushmm.org/online/hsv/person_view.php?PersonId=8255928

Date of Birth: 27 Aug 1903
Place of Birth: Harlingen
Last Residence: Amsterdam
Date of Death: 6 Dec 1944
Prisoner Number: 99508
Prisoner Group: HOL. JUD.
Source: International Tracing Service (ITS)

By establishing the date of death of Alexander van Gelder the official date (the 15th of March 1945) is maintained as stated after the war by the Dutch Department of Justice.

The official Stutthoff Database mentioned the 6th of December 1944 as the date of death of Alexander van Gelder.