His birth index:

Name:                              Mother's Maiden Surname:
DRUMMOND, JAMES GEOFFREY POWYS     FAIRBROTHER  
GRO Reference: 1889  S Quarter in EASTBOURNE  Volume 02B  Page 78

His birth date is known from a form of his father’s Indian pay records.
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In 1939 he, with the same birth date as on his father Indian military record, was with his apparent wife and three sons, at 156 Pinner Road, Watford, Herts:

                                                          Marital   Schedule
First name(s)  Last name(s)  Birth date  Sex  Occupation  status   Main  Sun
James G P  Drummond  27 Jul 1889  M  Major Indian Army (Retired)  M  94  1
Elsie      Drummond  25 Jan 1896  F  Unpaid Domestic Duties       M  94  2
John A G   Drummond  24 Sep 1930  M  At School                    S  94  3
James M    Drummond  16 May 1933  M  At School                    S  94  4
David A    Drummond  27 Oct 1936  M  Under School Age             S  94  5
Margaret   Schrodir  21 May 1867  F  School Reacher (Retired)     S  94  6

1939 ref: RG101/1643C/008/12
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Three children above can be half found in the birth indices:

1. John A G Drummond:

Name:                                Mother's Maiden Surname:
DRUMMOND, JOHN ALEXANDER GIRAULT     TAYLOR  
   GRO Reference: 1930  M Quarter in ST. PANCRAS  Volume 01B  Page 58

   But note that this birth is registered six months before the birth date given in 1939 and that the mother’s maiden name is given as Taylor.

   However there is the birth of a John B G Drummond with a Matheson mother in 1930, curiously only available on FreeBMD and FindMYpast but not on the online GRO index:James Michael

   Surname   First name(s)  Mother    District   Vol  Page
   Births Dec 1930   (>99%)
   Drummond  John B G       Matheson  Aylesbury  3a   1589

   So this is the registration index to use and send a correction to the online                                                                                  GRO. (Done.)

2. James M Drummond:

   Name:                       Mother's Maiden Surname:
   DRUMMOND, JAMES MICHAEL     MATHESON  
   GRO Reference: 1933  J Quarter in HAMPSTEAD  Volume 01A  Page 738

   This birth registration agrees with the 1939 birth date.

3. David A Drummond:

   No record on the online GRO index as it does not include 1936 yet, so from FreeBMD:

   Surname   First name(s)  Mother    District  Vol  Page
   Births Dec 1936   (>99%)
   DRUMMOND  David A        Matheson  Battle    2b   48

   This birth registration agrees with the 1939 birth date.

A search on FindMyPast for all Drummond births with a Matheson mother from 1929 to 1949 produces the same three registrations:

Last name  First name(s)  Year Of Birth   Location
Drummond   John B G       1930            Aylesbury, Buckinghamshire
Drummond   James M        1933            Hampstead, London
Drummond   David A        1936            Battle, Sussex
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His death index:

First name(s)  James G P
Last name      Drummond
Gender         Male
Birth year     1889
Age            77
Death quarter  4
Death year     1966
District       Watford
County         Hertfordshire
Volume         4B
Page           378
Country        England
Record set     England & Wales Deaths 1837-2007
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His probate index:

1967
DRUMMOND James Geoffrey Powys of 158 Pinner Road Watford Hertfordshire died 5 December 1955  Probate London 9 January to Elsie Drummond widow  £3654.

Will ordered.
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Their marriage index:

First name(s)       James G P
Last name           Drummond
Marriage quarter    2
Marriage year       1929
Marriage Finder     James G P Drummond married one of these people
                    Ilse Matheson
Spouse's last name  Parriss Or Matheson
District            Aylesbury
County              Buckinghamshire
Country             England
Volume              3A
Page number         2314
Record set          England & Wales Marriages 1837-2005
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Her last name of ‘Parriss Or Matheson’ needs looking into.  FreeBMD usually has the best information.  But no hint on FreeBMD, merely that two surnames were given at marriage.

I have searched FindMyPast for any other entry in any record for both Ilse Matheson and Ilse Parriss with a birth date of 1896±1 year anywhere in FMP’s world records; again only her marriage is on record.

Ancestry is slightly better in that it has an Ilse Forge Matheson in the 1911 census of Canada for Nova Scotia.  But a record for a Ilse Parriss, wife of John Westwood Parriss who was on Territorial Army records from 14.10.145 to 12.5.16 and they had a home address in Bushey, Herts.

John had enlisted for the Inns of Court O.T.C. and took thee oath in 10 Stone Buildings, Lincoln’s Inn, London.  He was discharged on 12 May 1916 as ’not being likely to become and efficient soldier (on medical grounds).   He was recorded as being a chartered accountant and their address was: Charteris, Maryhill Road, Bushey Herts & New Zealand(?).  He had 213 days of military service and was discharged on 17th May 1916. In 1917 he was given a ‘War Badge and Ceertificate’ which he received at 22 St Albans Crescent, Bournemouth.  In April 1916 he was admitted to hospital in Aylesbury with Pulmonary Tuberculosis; he stated he had had a previous attack in 1910 and the new illness was the cause of his discharge.  He was born around 1890.

He was baptised on 8th July at Christ Church Brondesbury, Brent.  His was was recorded to be 5th October 1887.  His parents were John William and Selina Parriss; his father was a Gent.  They lived at Adagh(?).  His birth was registered in Hendon district in Q4 of 1887.

In Q4 of 1913 John W Parriss married Ilse Hoegerstaedt in Hendon district.  There were other marriages of John W Parris but no other to an Ilse.

In 1921 a John Westwood Parriss was in Hendon in a large household.  I have not bought this yet.

No death found for him.
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In 1921 no sign of Ilse Parriss or Hoegerstaedt or Matheson in England.
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