Her baptism index:

First name(s) Sarah
Last name Longman
Birth year 1820
Baptism year 1820
Baptism date 25 Sep 1820
Baptism place Sherborne
Parents' name(s) Daughter of John & Sarah
Father's first name(s) -
Mother's first name(s) -
Notes Druggist
County Dorset
Country England
Record set Dorset Baptisms
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In adult life she consistently used the second forename of ‘Churchill’.
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In 1961, she was back from a military tour in East Indies and living in Wandsworth with her three children and only surviving unmarried sister:

First name(s) Last name Relationship Marital status  Gender  Age  Birth year  Occupation Birth place

William D Grant Head Married Male 44 1817 Captain H D East India Army  Scotland
Sarah C Grant Wife Married Female 40 1821 - Marylebone [sic], Dorset
Flora M Grant Daughter Unmarried Female 8 1853  Scholar  East Indies
Emily S Grant Daughter Unmarried Female 5 1856  Scholar  East Indies
John H Grant Son Unmarried Male 2 1859 - London, Middlesex
Mary C Longman Sister In Law Unmarried Female  49  1812  -  Sherborne, Dorset
Kezia Haxsath Servant Unmarried Female 42 1819  Nurse  Devon
Sophia Pittack Servant Unmarried Female 24 1837  Housemaid  Middlesex
Frances Stevens Servant Unmarried Female 29 1832  Cook  Soho, Buckinghamshire

Census details
First name(s) Sarah C
Last name Grant
Relationship Wife
Marital status Married
Gender Female
Age 40
Birth year 1821
Occupation -
Birth town Marylebone
Birth town as transcribed MARYLEBONE
Birth county Dorset
Birth county as transcribed DORSET
Birth place (other) England
Birth place other as transcribed -
Street Balham
Parish Streatham
City or borough -
County London, Surrey
Country England
Municipal ward -
Parliamentary borough -
Ecclesiastical district St Mary
Registration district Wandsworth
Enumeration district 3
Archive reference RG09
Piece number 375
Folio number 35
Page number 6
Family member last name GRANT, LONGMAN, HAXSATH, PITTACK, STEVENS
Family member first name(s) FLORA, EMILY, JOHN, MARY, KEZIA, SOPHIA, FRANCES, SARAH, WILLIAM
Record set 1861 England, Wales & Scotland Census
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Initially she was not found in 1871 but then she was and had lost a couple of years off her true baptism record.  They had another two sons:

First name(s) Last name Relationship Marital status  Gender  Age  Birth year  Occupation Birth place

William D Grant Head - Male 54 1817 First Col Infantry Retd  Scotland
Sarah S Grant Wife - Female 49 1822 - Dorset, Sherborne
Flora A Grant Daughter - Female 18 1853 - East Indies
Emily S Grant Daughter - Female 15 1856 - East Indies
John H Grant Son - Male 12 1859 - Middlesex
William C Grant Son - Male 9 1862 - Surrey, Buxham
Harry K Grant Son - Male 7 1864 - Kent, Deal
Sarah S Fogg Governess - Female 20 1851 - Kent
Eliza E Holiday Servant - Female 37 1834 - Kent
Mary MacKerall Servant - Female 18 1853 - Kent
Elizabeth Evans Servant - Female 18 1853   -  Monmouthshire, Wales

Census ref:
Registration district: Clifton
Archive reference RG10
Piece number 2541
Folio 5
Page 2
Record set 1871 England, Wales & Scotland Census
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Her death in 1903:

First name(s) SARAH CHURCHILL
Last name GRANT
Gender Female
Birth day -
Birth month -
Birth year 1821
Age 82
Death quarter 1
Death year 1903
District RUGBY
County Warwickshire
Volume 6D
Page 355
Country England
Record set England & Wales deaths 1837-2007
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In 1891 she was in Rugby, a widow, born in Sherborne, Dorset and with her daughter Emily:

First name(s) Last name Relationship Marital status  Gender  Age  Birth year  Occupation Birth place

Sarah C Grant Head Widow Female 69 1822 - Sherborne, Dorset
Emily S H Grant Daughter Single Female 34 1857  -  India
Mary Collins Servant Married Female 56 1835 - Devon
Lucy Bennett Servant Married Female 23 1868 - Kenilworth, Warwickshire

Census Ref:
Registration district Rugby
Archive reference RG12
Piece number 2457
Folio 129
Page 83
Record set 1891 England, Wales & Scotland Census
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1901 census not found for her, but the search did work for Emily, and there Sarah was!  (She had lost a year and was down as born in 1823, so escaped the search for 1820 plus or minus 2 for her birth!):

First name(s) Last name Relationship Marital status  Gender  Age  Birth year  Occupation Birth place

Sarah C Grant Head Widow Female 78 1823 Living On Own Means  Sherborne, Dorset
Emily S H Grant Daughter Single Female 44 1857  -  Secundrabad, India
Jane Moore Servant Single Female 25 1876 Cook Domestic  Leamington, Warwickshire
Annie Winders Servant Single Female 24 1877 Parlour Domestic  Histon, Cambs

Census ref:
Archive reference RG13
Piece number 2918
Folio 84
Page 10
Record set 1901 England, Wales & Scotland Census
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She had a last son born after the 1861 census.  From the family memorial in Rugby:

“WILLIAM ARTHUR CHURCHILL GRANT Major, RMLI (son of the late Col W D GRANT) died April 11 1906 aged 44 years.”
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From the Probate index:

GRANT Sarah Churchill of St Ronans Rugby Warwickshire widow died 28 March 1903 Probate London 6 June to Emily Sarah Howard Grant spinster and Charles leftwich Oldfield bartlett and Edward Whitely Bartlett solicitors Effects £13,150 7s 8d. Resworn £16836n-5-1.
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Their marriage index:

First name(s) SARAH CHURCHILL
Last name LONGMAN
Marriage quarter 3
Marriage year 1849
Registration month -
MarriageFinder™ SARAH CHURCHILL LONGMAN married
                 WILLIAM DAVIS GRANT
District ST. GEORGE HANOVER SQUARE
District number -
County London
Country England
Volume 1
Page 49
Record set England & Wales marriages 1837-2008
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On the marriage register is recorded:

year: 1849
Place: St Michael’s church,
Parish:  District parish of St Peter, Pimlico, Mx
No:      110
Date:    August 16th
Groom:   William Davis Grant
   Age:        Full
   Condition:  Bachelor
   Rank:       Capt 50 Regt M.N.I.
   Residence:  5 Coleshill Street
   Father:     John Howard Grant
   Father Rank: Esquire
Bride:   Sarah Churchill Longman
   Age:        Full
   Condition:  Spinster
   Rank:       ... [blank]
   Residence:  8 Westbourne Place
   Father:     John Longman
   Father rank: Esquire
Married in the District church by Licence by L S Green
Signatures:  William Davis Grant, Sarah Churchill Longman
Witnesses:   Thos Coster,  M C Longman  John ??????

Now for the licence...  But not in Foster’s London marriage Licences 1521-1869.
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