The eldest son of Benjamin Jr., and the Second Generation of Martin Brothers Funeral Directors, Derek was born and raised in Lethbridge. When WW II broke out, Derek enlisted and served with the 112th Light Anti-Aircraft Battery with the Canadian Armed Forces in Europe throughout the war. He attained the rank of Sergeant. After the war, Derek returned to Lethbridge where he worked at Martin Brothers Funeral Chapels with his Father, Ben, and Uncle Harry.