Abraham (Harry) Slager was a son of Gerson Slager and Betta Spits. He was arrested and deported in 1941 because of his openly expressed anti-German sentiments. He had two children with his first wife Sophia Jacobs (who died before the war), who survived the war. With his second wife he had his son Max.
For a biographical note see: H.E. Dominicus, Mauthausen. Een gedenkboek (2e herziene en uitgebreide druk; Amsterdam 1999) 142.