At marriage in Jan 1914, she was 23 so born around 1890 and her father was the late Patrick Whelan.  This should lead to finding her in the 1891, 1901 and 1911 censuses.

This led to clearly finding her in the 1901 census with her widowed father, a load of siblings including a married sister with her husband, head of house, and newborn child:

First name(s) Last name Relationship Marital status  Sex  Age  Birth year  Occupation  Birth place
John McPhillips Head Married Male 29 1872 Laborer Blast Furnace  Washington, Durham
Kate McPhillips Wife Married Female 27 1874  -  Middlesbrough, Yorkshire
Annie May McPhillips Daughter - Female 0 1901  -  North Ormesby, Yorkshire
Patrick Whelan Father-In-Law Widower Male 53  1848  Laborer Blast Furnaces  Ireland
William Whelan Brother-In-Law Single Male 23  1878  Laborer Blast Furnaces  North Ormesby, Yorkshire
Joseph Whelan Brother-In-Law Single Male 21  1880  Rivetter  North Ormesby, Yorkshire
John Whelan Brother-In-Law - Male 15 1886  Rivet Heater (Shipyard)  North Ormesby, Yorkshire
Timothy Whelan Brother-In-Law - Male 13 1888  Errand Boy (Shop)  North Ormesby, Yorkshire
Bernard Whelan Brother-In-Law - Male 13 1888  Errand Boy (Shop)  North Ormesby, Yorkshire
Mary Whelan Sister-In-Law - Female 11  1890  School  North Ormesby, Yorkshire
Gertrude Whelan Sister-In-Law - Female 6  1895  School  North Ormesby, Yorkshire

Address and ref:
House number 1
Street High Street
Town North Ormesby
County Yorkshire, Yorkshire (North Riding)
Archive reference RG13
Piece number 4587
Folio 25
Page 42

1901 Ref: RG13, piece 4587, folio 25, p. 42
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I have tried to find the birth registrations for the children of Mary’s parents.  William and Joseph’s births are not to be found.  John, Timothy, Bernard, Mary and Gertrude are all to be found with a mother’s name of Downey and a registration district of Middlesbrough.  So Patrick Whelan married a Downey and Mary’s birth index was:

First name(s) MARY
Last name WHELAN
Birth year 1890
Birth quarter 2
Registration month -
Mother's maiden name Downey
District Middlesbrough
County Yorkshire
Country England
Volume 9D
Page 594
Record set England & Wales Births 1837-2006

A confirmation of this is that the witnesses to Mary’s marriage were a H Downey and W A Downey, presumably relatives of her mother.  At the time of Mary’s marriage both her parents had died.

I cannot find the marriage of Mary’s parents on English records.  Might they have married in Ireland?
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For her death, her last child was born in 1921 and she is not to be found clearly in the 1939 Register.  But nor can her death be found between 1921 and 1939, let alone after 1939.  Did she remarry?  In 1923 a Mary Boynton married a John Berry in Stockton, but nothing can be found in the 1939 register for a Mary berry born in 1890, nor can any Mary berry deaths be found before that.

I cannot find her death index!
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Their marriage index:

First name(s) ROBERT
Last name BOYNTON
Marriage quarter 1
Marriage year 1914
ROBERT BOYNTON married one of these people
Mary Whelan
Spouse's last name Whelan
District Middlesbrough
County Yorkshire
Country England
Volume 9D
Volume as transcribed 9D
Page number 911
Record set England & Wales Marriages 1837-2005
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Their marriage register entry is:

Place:      St Mary’s Cathedral, Middlesbro, Middlesbro’ & Yorks
Cert No:    14
Date:       10 Jan 1914
His name:   Robert Boynton
His age:    31 yrs
His status: Bachelor
His job:    Ironworks labourer
His abode:  7 Frederick Terrace, Haverton Hill
His father: John Boynton (deceased)
His Father: Iron Foundry labourer
Her Name:   Mary Whelan
Her age:    23 yrs
Her status: Spinster
her job:    -
Her abode:  25 Ash Street, Middlesbro’
Her father: Patrick Whelan (deceased)
Her father: Blast furnaceman

Signatures:  R Boynton,  M Whelan
Witnesses:   H Downey,  M A Downey
Celebrant:   P Lynn, R.CX. Priest
Registrar:   Jas Hayton

Note: Her mother was Ann(e) Downey.  So their marriage witnesses have to be her relations, cousins, aunts, uncles or even grandparents.
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