His birth index:

Name:                       Mother's Maiden Surname:
STOPFORD, HORACE ROBERT     BIRCH REYNARDSON
GRO Reference: 1855  D Quarter in MARYLEBONE  Volume 01A  Page 364
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No baptism found
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In 1891 they were at Lower Sloane Street, Chelsea, London with a daughter and a son:

First name(s)  Last name  Relationship  Marital status  Sex  Age  Birth year  Occupation  Birth place
Horace R    Stopford  Head  M  M  35  1856  Captain Coldstream guards  London, Middlesex
Marguerita  Stopford  Wife  M  F  29  1862  -                          Dublin, Dublin, Ireland
Norah G     Stopford  Daur  -  F   7  1884  -                          London, Middlesex
Robert M    Stopford  Son   -  M   0  1891  -                          Windsor, Berkshire
George      Ashley    Serv  S  M  30  1861  Private Coldstream guards  Lowe, Kent
Harriet     Phillips  Serv  S  F  41  1850  Cook                       Ombersley, Worcestershire
Sarah       Coles     Serv  S  F  22  1869  General servant            Brightwell, Berkshire
Amelia      Pearce    Serv  S  F  36  1855  Nurse                      Gloucester, Gloucestershire
Louisa      Skett     Serv  S  F  17  1874  Nurse maid                 Westminster, Middlesex

Ref:
Archive reference  RG12
Piece number       63
Folio              19
Page               36
Combined:          1891 ref: RG12, piece 63, folio 19, p. 36

Note that Norah’s age is down at 7 whereas she was definitely born in 1889, below, and the age entered could just as easily be 2.
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Their children from a search for Stopford births with a MacDowell mother’s maiden name:

Name:                         Mother's Maiden Surname:
STOPFORD, NORAH GRACE EDEN MACDOWEL  
GRO Reference: 1889  S Quarter in CHELSEA  Volume 01A  Page 340
STOPFORD, ROBERT MAURICE      MACDOWELL  
GRO Reference: 1890  S Quarter in WINDSOR  Volume 02C  Page 423

And the search was slightly hindered by the lack of the second ‘l’ in the mother’s maiden name for Norah.
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There is a record of his death in the GRO but the index has very little information.  The series is “Gro Natal & South African Forces Death (1899 To 1902)”, page 172, line 51.
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His probate index:

1900
STOPFORD Horace Robert of “Glenedin” Sheringham Norfolk lieutenant-colonel in the Coldstream-guards died 28 November 1899 at Modder-river South Africa  Administration London 28 February to Marguerite Louisa Greathed Stopford widow  Effects £5277 18s. 7d.
Revoked 26th January 1903-

Why revoked?  Possibly because his will was found.

And in 1903, another entry:
STOPFORD Horace Robert of “Gleneden” Sheringham Norfolk lieutenant-colonel in the Coldstream-guards died 28 November 1899 at Modder River Cape Colony South Africa  Administration (with Will) London 13 March to Marguerite Louisa Greathed Stopford widow
Effects £5277 16s. 9d.  Former grant February 1900.

Will ordered.
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Apparently there had been a bit of a tussle in the courts as to who was his Administrator, was it his wife or a friend who had been left with a difficulet instruction to handle?  It was his wife.

I still am not sure what the will was, but it would have been nice to have seen some acknowledgement of his children.
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From the Nottingham Evening Post of 4 December 1899

“                  A GALLANT OFFICER
“  Lieutenant-Colonel Horace Robert Stopford of the 2nd Coldstream Guards, was well known at the Cromer and Sheringham Golf Club.  It seems but a few days ago that he was playing on those links.  He was a most lovable man, liked by all who knew him, and although he was an accomplished soldier and every inch of him and ideal Guardsman, yet he had no “side”.  His company was much sought by all who liked good fellowship and pleasant conversation.  There is universal grief in the district at his untimely death, and the keenest sympathy is felt for the widow who is living at Sheringham, and her two children.  These sad and lamentable incidents bring vividly to our senses the horrors of war.  His splendid and handsome physique will be much missed by his many friends.”
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And from FindMyPast’s “Angle-Boer War Records 1899-1902”:

First name(s)   Horace Robert
Last name       Stopford
Age             44
Rank            Lieutenant-Colonel
Regiment        2 Battalion Coldstream Guards
Rolls           WO100/164 page 1
Year            1899-1902
Biography
   He was killed at the battle of Modder River November 28th, 1899. He was born in October 1855, and educated at Eton. He entered the 46th Foot in June 1874, was transferred to the Coldstream Guards as Lieutenant August 1875, was promoted Captain October 1885, Major November 1893, and Lieutenant Colonel to command the 2nd Battalion, February 1899. From 1881-85 he was ADC to the General Officer Commanding the Forces in Ireland, and from 1887-89 was Commandant of the School of Instruction for Auxiliary Forces at Wellington Barracks. His battalion, on arrival in South Africa, joined the Kimberley Relief Force, under Lieutenant General Lord Methuen, and took part in the battles of Belmont and Graspan. While leading his battalion at Modder River, Lieutenant Colonel Stopford was killed by one of the first shells fired by the Boers in this action. He is mentioned in the report of Major General Sir H Colville, concerning the battle of Belmont "the advance of his battalion was distinctly well performed". Image in Aberdeen Press and Journal 18991206. Source: LP
Memorials
   St Paul's Cathedral. South-west end.  Plaque coldstream Guards, City, London, England; Castle Meadows. County Memorial, Norwich, Norfolk, England; Holy Trinity. North & south gallery. Panels. Household Cavalry & Guards, Windsor, Berkshire, England; Eton College Chapel Lupton's Chantry. Old Boys, Eton, Berkshire, England
Event detail  Killed on 28/11/1899 at Modder River
Event unit    2 Battalion Coldstream Guards
Event source  SAFF
Country       Great Britain
Literary references
   The Transvaal in War and Peace: N. EdwardsI13 CG20; cm Transvaal War Album39; Diaries of the Siege of Ladysmith/33; Our Heroes of the South African War; From Aldershot to Pretoria: W. E. Sellers 71;87; Etonians in the Boer War 56; The Last Post being a roll of all officers; HBI/149; Aberdeen Press and Journal
Notes        [Anglo-Boer War Memorials Project]  QSA Clasps: B,MR
Record set   Anglo-Boer War Records 1899-1902
Category     Military, armed forces & conflict
Subcategory  Boer Wars
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From the image of the Register, thanks to the Irish Genealogy site (free!), transcript by me:

“1884.  Marriage  solemnized at Registrar’s Office in the City of Dublin in the Divn. Dublin …(?)
“No:            35
“When married:  15th day of April 1884

                   His                           Hers
                   ===                           ====
“Name:          Horace Robert Stopford        Margaret McDowell
“Age:           Full                          Full
“Condition:     Bachelor                      Spinster
“Profession:    Gentleman                     -
“Residence:     Royal Hospital, Kilminham(?)  13 Merrion Square
“Father:        Robert Stopford (dec)         Benjamin G McDowell
“Father’s job:  Gentleman                     M.D.

“Married in the Registrar’s Office according to provs. of Act “7&8”, cap 51 on licence
“  by me Thos W Bowler, regr.

“This Marriage was solemnized between us,  Horace Robert Stopford, Margaret MacDowell

“In the Presence of us, Benj G McDowell M.D.,  George Bowler
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