Source: Medal listing at Arctic Medals . Com.
Family Search: When Private David Duncan was born on 1 September 1882, in Inverkeilor, Forfarshire, Scotland, United Kingdom, his father, William Duncan, was 31 and his mother, Margaret Cumming, was 18. He had at least 1 son and 1 daughter with Edith Britton. He immigrated to Canada in 1913. He registered for military service in 1915. In 1915, at the age of 33, his occupation is listed as gamekeeper. He died on 8 February 1928, in Airdrie, Alberta, Canada, at the age of 45, and was buried in Burnsland Cemetery, Calgary, Alberta, Canada.
History of the 18th Battalion CEF, "The Fighting Eighteenth" 