Source: Per post by Allan Miller at 18th Battalion Facebook Group.
Under age.
Originally attested on November 30, 1915, that his date of birth was June 4, 1897. Notation in file indicates he was born this date in 1901 making him 14 years, 5 months, and 27 days old at time of enlistment. He was 5′ 2.75″ tall at enlistment. He was 5′ 6″ at discharge on August 2, 1918.
He was discharged as a minor and had served with the 18th Battalion being wounded on April 6, 1918
War Diary of the 18th Battalion CEF 