No information has been found for on her birth.  The best we know is that at marriage she said she was 18 and then in the 1911 census she said for her birth that that the place was “Assiaghur Indian Resident”; the latter probably means that she was definitely born in India.  An interesting extra to this is that her brother, five years younger than her, was with them in the 1881 census and was born in Ireland, so this may be where she and her family came from.
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In 1901 Emilie was at Oaklands, Groombridge, Withyham, East Grinstead, Sussex with her elder son Douglas and four daughters and a guest, Helen Bayly (who she?):

First name(s)  Last name  Role  Marital status  Sex  Age  Birth year  Occupation  Birth place
Emilie   Drummond  Head  W  F  44  1857  Living on own means  India
Ethel    Drummond  Daur  S  F  24  1877  -                    India
Elsie    Drummond  Daur  S  F  22  1879  -                    India
Douglas  Drummond  Son   S  M  20  1881  -                    Tunbridge Wells, Kent, England
Eileen   Drummond  Daur  S  F  18  1883  -                    Arabia
Gladys   Drummond  Daur  S  F  13  1888  -                    India
Helen    Bayly     Vstr  S  F  63  1838  Living on own means  Midhurst, Sussex, England

Ref:
Archive reference  RG13
Piece number       903
Folio              26
Page               16
Combined:          1901 ref: RG13, piece 903, folio 26, p. 16    
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In 1911 she was down to one daughter and that one was married but she still had Helen E Bayly with her for company and still at Oaklands Groombridge Sussex, Withyham, Sussex:

First name(s)  Last name Role  Marital status  Sex  Age  Birth year  Occupation  Birth place
Emilie K M E  Drummond  Head  W  F  54  1857  Private means    Assiaghur Indian Resident
Helen E       Bayly     Gust  S  F  73  1838  -                Midhurst Sussex
Gladys M P    Hennell   Daur  M  F  23  1888  -                Satara Indian Resident
Rose          Coppard   Serv  S  F  27  1884  General servant  Rusthall Kent

  1911 ref: RG14  PN4974  RG78  PN218  RD75  SD1  ED2  SN130

Gladys reported that she had been married for two years and had no children.
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She is in the 1921 census but I can see no need to find the details of this.  At least it means she died in or after 1921.
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The mystery about Leopold Douglas Powys Drummond, see his father’s Notes, has been resolved, above.  But there remains a mystery about Herbert Cecil Powys Drummond, born in India in 1877.  Nothing has been found about him since.

The answer is that he died in 1881 aged 3:

Name: Age at Death (in years):  
DRUMMOND, HERBERT  CECIL POWYS 3  
GRO Reference: 1881  M Quarter in WANDSWORTH  Volume 01D  Page 378
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So their seven children are, with the reservation that the two Eileen baptisms need sorting out:

Name                  Birth Yr  Birth Place             Death Yr   Death Place
Ethel Louisa Powys     1876     Ahmedabad, Bombay
Herbert Cecil Powys    1877     Ahmedabad, Bombay
Elsie Kathleen Mary    1879     Belgaum,St Mary, Bombay  1881      Wansdsworth, Mx
Leopold Douglas Bell   1881     Tunbridge Wells, Kent
Eileen Amy Powys       1882     Aden                   }
Eileen Amy Powys       1882     Bombay,St Mary, Bombay }
Gladys Margaret Powys  1887     Mahableshwar, Bombay
James Geoffrey Powys   1889     Eastbourne, Sussex

This is confirmed in the entries for them in the Bombay Donations Fund, see her husband’s Notes, and includes their birth dates.

In one of the pages on her husband there is a record of a Lt-Col James Fairbrother who had joined the Fund on 21st Nov 1845, six years senior to her husband.
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Her death, over forty years after her husband’s, index:

Name:                                         Age at Death (in years):  
DRUMMOND, EMILIE KATHERINE MARY ELIZABETH     79  
GRO Reference: 1936  D Quarter in EASTBOURNE  Volume 02B  Page 138
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Her probate index:

1937
Drummond Emilie Katherine Mary Elizabeth of Oaklands Groombridge Sussex widow died 15 December 1936 at Leaf Hospital Eastbourne  Probate Lewes 30 January to James Geoffrey Powys Drummond retired major Indian army.  Effects £3598 1s. 3d.

Will ordered.
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From the British India Office via FindMyPast (thanks for the image, their marriage register, transcript by me:

“Marriage solemnized at Mhow

When married:
  Year:   1875
  Month:  November
  Day:    1

                   His                        Hers
                   ===                        ====
Names:          James Houlbrooke           Emilia Katherine Mary Elizabeth
Age:            42                         18
Condition:      Bachelor                   Spinster
Profession:     Major, Bombay Staff Corps  -
Residence:      Mhow                       Mhow
Father:         James Drummond             James Fairbrother
Signatures:     J H Drummond               E K E M Fairbrother
Witnesses:      J Fairbrother,             J Kefferman

Banns/Licence:  Licence
Celebrant:      Chas J Waterhouse, M.A. Chaplain

I Edward Gabriel Davis do hereby certify the foregoing are true and faithful copies of all the entries in the Register of Marriages kept at Christ Church Mhow as therein entered and made between the first day of October and the thirtyfirst day of December 1875.
  Witness my hand
    Edward G Davis
      Chaplain of Mhow

Mhow Jany 1st 1876
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