Source: Per article in London Advertiser dated March 14, 1916, relating his return home after wounding.
Find-A-Grave: Note this man is listed under first name John.
Family Search: Joseph Robert Strong was born on 28 August 1873, in Banbridge, County Down, Northern Ireland, United Kingdom as the son of Joseph D Strong and Mary Lilburn. He lived in Moose Jaw, Moose Jaw No. 161, Saskatchewan, Canada in 1921. He registered for military service in 1914. In 1914, at the age of 41, his occupation is listed as labourer. He died on 2 March 1937, in Vancouver, British Columbia, Canada, at the age of 63, and was buried in Mountain View Cemetery, Vancouver, British Columbia, Canada.
History of the 18th Battalion CEF, "The Fighting Eighteenth" 