Source: Per post of headstone of this soldier by Greg Melanson from the 18th Battalion Facebook Group.
Family Search: Private William Sewell was born on 12 May 1885, in Cumberland, England, United Kingdom as the son of William Sewell. He had at least 1 son with Elizabeth. He lived in London, Ontario, Canada in 1923. He registered for military service in 1915. In 1915, at the age of 30, his occupation is listed as labourer. He died on 26 April 1944, at the age of 58, and was buried in London Township, Middlesex, Ontario, Canada.
History of the 18th Battalion CEF, "The Fighting Eighteenth" 