Psychiatrist, Professor of Social Psychiatry, University of Leiden, The Netherlands; Author and noted authority on Suicide.
During WWII: Psychiatrist at Het Adeldoornsche Bosch, Netherlands Jewish psychiatric facility until January 1943 when German occupiers closed the facility and sent patients away to concentration camps. Dr Speijer was ordered by German authorities to work as a medical psychiatrist at Westerbork transit camp, which was used as a transit facility to other camps. He and his wife Renee survived the Holocaust because of his medical expertise. They were liberated in April 1945 from Westerbork. Sadly, Nico's mother Isabella Rebecca (Tas) Speijer died at Westerbork in 1943.
https://www.niodimagelab.nl/apeldoornsche-bosch
Nico and Renee Speijer died together by suicide in 1981 when Nico was ill with terminal cancer and in great pain and wife Renee was disabled. They had no children.
Source: The Significance of Nico Speijer's Suicide: How and When Should Suicide Be Prevented? - Diekstra - 1986 - Suicide and Life-Threatening Behavior - Wiley Online Library