Gideon was known affectionately as "Gi" by his family and friends. His parents were descended from the Huguenots, French Protestants who came to the Netherlands in the 16th and 17th centuries. Gi had two brothers and two sisters, and his father worked in the insurance business.
1933-39: Gi had a large circle of friends, both Christians and Jews, and after school they all liked to get together. He and his friends enjoyed taking bike trips, having parties, and playing records. In the mid-1930s his parents joined the Dutch Nazi party because it appeared to them, at first, to offer a good, orderly political system. They quickly abandoned the party, however, when they saw how brutally its members behaved.
1940-42: Gi completed a training course to be an actuary, and was working at an insurance company. Then on May 10, 1940, the Germans invaded the Netherlands, and by the 18th German troops had occupied Amsterdam. Gi and his brother began to work for the Dutch resistance. His parents helped to hide Jews. On Sunday, August 2, 1942, Gi and his brother were arrested and imprisoned.
Gi was executed by the Nazis on October 1, 1942, along with his brother and 18 other resistance fighters. He was 20 years old.