Source: Per research by 160th Battalion Facebook Group. Confirmed served with 18th Battalion.
Family Search: When Private John Percy Roulston was born on 18 October 1891, in Huron-Kinloss, Bruce, Ontario, Canada, his father, Johnston Roulston, was 37 and his mother, Mary Helm, was 28. He married Edith May Dark on 2 July 1928, in Grey Township, Huron, Ontario, Canada. They were the parents of at least 2 sons. He lived in Ontario, Canada in 1891 and Bruce, Ontario, Canada for about 10 years. He registered for military service in 1916. He died on 15 August 1942, in Stratford, Perth, Ontario, Canada, at the age of 50, and was buried in Avondale Cemetery, Stratford, Perth, Ontario, Canada.
History of the 18th Battalion CEF, "The Fighting Eighteenth" 