Source: Per personal message from Allan Miller at Facebook.
Find-A-Grave
Family Search: When Robert Douglas was born on 8 July 1874, in Petrolia, Lambton, Ontario, Canada, his father, James Douglas, was 25 and his mother, Margaret Moore, was 22. He married Emma Whitehouse on 5 November 1902, in Petrolia, Lambton, Ontario, Canada. They were the parents of at least 1 daughter. He lived in Lambton, Ontario, Canada in 1901. He registered for military service in 1915. In 1915, at the age of 41, his occupation is listed as driller.
Brother to Captain Walter David Perry.
War Diary of the 18th Battalion CEF 