Source: Michael Doyle Their Name Liveth For Evermore: The Great War Roll of Honour for Leicestershire and Rutland.
His enlistment documents record that he gave his sister, Mrs Jas. Slater of Grand Valley Gardens, S. Hill, Moose Jaw, Saskatchewan, Canada as his next of kin. He gave his trade or calling as Canadian Pacific Railway Shed Foreman. He stated he was unmarried. A second enlistment document gave his wife, Mrs W. Marriott of High Street, Knipton, Grantham, Leicestershire, England as his next of kin. Information taken from his medical examination shows that he was 5 foot 6 inches in height and had a chest measurement of 34 to 37 inches. His complexion was described as fair with blue eyes and brown hair. He gave his religion as Church of England. The village and church memorial’s incorrectly show his name as Walter.

Source: Leicestershire War Memorials Project.
"Walter Marriott was born according to the memorial on the family gravestone on 3/4/1886 (the 1891 census says he was 5). He appears to have moved to Moose Jaw, Saskatchewan, around 1910. He joins the Canadian Expeditionary Force on 11/9/1915, giving his “sister” as Mrs James Slater of Moose Jaw and his own name as William (dropping Walter). The same forms are later updated to reflect his marriage to “Mrs W Marriott” of Main St, Knipton. This is actually Annie L A Marriott (b1892); the marriage was registered in Grantham in January 1916, so between then and enlisting in September 1915, he moved back to the UK. He was in Belgium by Autumn 1917, and was killed “in the trenches South West of Passchendaele”. He’s commemorated on the Menin Gate."
(Information from C Haywood, 13/12/2023)