John Louby (Darroch) - birth was registered Dec.qtr.1895 Preston, Lancashire (as confirmed on 1901 census) - this would fit with a birthdate of 14th October but was 3 years earlier than what you state.
According to service records John Tamar Louby (in 6th Dragoon Guards) married Euphemia Ann Storrock Thynne 5/1/1895 Register Office, York. To confirm above, son John is shown as born 14/10/1895. When John enlisted in 1885 his next of kin is given as brother Thomas Louby (also in army). When Thomas himself enlisted in 1883 he gave his nok as brother JAS. Louby who was in the 1st Bn. Rifle Brigade.
In 1881 John - 10 yrs old - bc.1871 Woolwich, Kent is in Royal Military Asylum, Chelsea. This appears to be a military school suggesting his father was a military man too. Also in the school is Thomas Louby 13, born Canada - ref. RG11 - 79 - 88 - 2. Both shown as scholars.
Have found a catholic baptism for Thomas Louby 5/2/1868 Basilque Notre Dame, Ottawa, Ontario, son of Thomas Louby and Jeanne Robb. It's written in French but think I've got parents name right.
1871 Census at 14 Lawes Wood Street, Woolwich, Kent - ref. RG10 - 778 - 39 - 18
Thomas Lowby (as transcribed) 29 Private Rifle Brigade b. Ireland
Jane Lowby 30 b. Scotland
James Lowby 5 b. Ireland
Thomas Lowby 3 b. Canada
John T. Lowby 7 mos. b. 'At Sea'.
So, although John Tamar Louby states he was born in Woolwich (where brought up) he was actually born at sea when family returning from Canada.
Thomas Louby 20 Private 29th Regt., son of James Louby, Tailor (deceased) and Mary, nee Barrie (deceased) married 13/4/1863 Ayr, Scotland to
Jane Robb 19 Domestic Servant, dau. of James Robb, Ostler and Janet, nee Thornton (deceased)
(marriage on Scotlands People).
Looks like Thomas Louby bc.1841 died Dec.qtr.1875 Winchester, Hampshire and Jane predeceased him bc.1844, d.Mar.1874 Farnham, Surrey (Winchester and Farnham both army sites) and explains how Thomas jnr and John T. were in the Military Asylum in 1881.
Annette