James Stocks was a man anxious to obscure his past. He told the RIC a pack of lies on his age and origin. He told the a pack of lies to the Canadian Army about his origin and his next of kin.. I think that he was proably born between 1871 and 1875 near Edinburgh.
The one, probably true fact, is that he had a sister Beatrice McGill in Canada with him. He tried to pass her off as his wife to the CEF Beatrice Stocks is a rare name in Scotland, There was a Beatrice Stocks born 1872, who married a James McGill in 1895 in Leith (the CEF record shows that her married name was McGill). Oddly there are no Beatrice Stocks in Scottish census records, but I found her as Beatrice Morgan. In the end I was able to get a lot about Beatrice, but could not get a birth or census records for James Stocks
1874 Mar 28. Born Canada in RIC His first offer to CEF was 1870 in Preston Pans, Scotland . He later gave his year of birth as 1867 to the CEF (There is James Stocks born Lasswade in 1868 in ScotlandsPeople but that birth gives the mother as Agnes, not Jane who was the mother of Bearice). Having followed the clues given in his CEF attestation, one can follow his sister Beatrice right back to her (illegitimate birth in 1872) It looks as if the mother of both siblings, Beatrice and James was born Jane Stocks, married a William Morgan in 1856. He died in 1871 after they had a number of children together. She then re-married to a David Campbell in 1875. So it looks as if Beatrice and James werre illegitimate children born between 1871 and 1875. We know Beatrice was 31 Oct 1872, so I would assume James was born between Sep 1873 and Dec 1875 (but I cannot get him in ScotlandsPeople)
A Private Ancesry tree gives his birth as 28 Mar 1871
1917 Jun 17. Enlisted in CEF. . It turned out that Beatrice was his Sister and he was (he said) a widower.Presumably to get a separation allowance. His father was William
1918 Apr 11 Discharged - unfit
1920 Oct 29. Joined as RIC no 75060 & ADRIC no 224 . ex-Soldier & Stoker
1920 Dec 20. Posted to J Coy
1921 Jan 3. Services dispensed with