Her birth index:

First name(s) WINIFRED Y
Last name SAUTTER
Birth year 1917
Birth quarter 3
Mother's last name COLE
District POOLE
County Dorset
Country England
Volume 5A
Page 335
Record set England & Wales births 1837-2006
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Is this her marriage?

First name(s) WINIFRED Y
Last name SAUTTER
Marriage quarter 2
Marriage year 1947
Registration month -
MarriageFinder™ WINIFRED Y SAUTTER married
WHIMSEY M LAUDON
Spouse's last name LAUDON
District PADDINGTON
County London
Country England
Volume 5D
Page 524
Record set England & Wales marriages 1837-2008

The only way to find out is to buy the certificate as it will have her father’s name on it.

No Laudon births in England and Wales.

But this marriage is confirmed by the fact that she used the surname of Laudon when she married Thomas Henry Parker in 1963.

In fact she was her mother’s beneficiary and was named by her mother as Winifred Yvonne Parker.
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No marriage found between Parker and Sautter but she clearly, from the MI, thought of herself as aligned with Henry Thomas Parker and had taken his surname at least as early as 1965 when her mother wrote her will.

Did she have any children?  It sounds as if her will must be bought to find out.
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Her death index (now that we know her adult surname):

First name(s) WINIFRED YVONNE
Last name PARKER
Gender Female
Birth day 25
Birth month 10
Birth year 1918
Age -
Death quarter 4
Death year 1974
District PENZANCE
County Cornwall
Volume 21
Page 0333
Country England
Record set England & Wales deaths 1837-2007
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Her will makes it obvious that she had no children herself.  She stated she had married Henry Thomas Parker, though this could have been in another country.  If he predeceased her she left everything to her stepson, one David Henry Parker, obviously her husband’s son by a former relationship.  So I deduce that she had no children and that she was the last of her line.
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Her probate index from the same house where her mother died two years previously:

PARKER Winifred Yvonne of Van Ruan Gorran St Austell died 19th November 1974 Probate Bristol 8 May [1975] £119503
750720734C
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Her M.I. index:

First name(s) WINIFRED YVONNE
Last name PARKER
Birth year 1917
Death year 1974
Age 57
Burial year 1974
Burial day 1
Burial month Dec
Place WARDOUR; RC CEMETERY
County Wiltshire
Country England
Notes b 21 Jul 1917 nee SAUTTER DE BEAUREGARDE wife of Henry Thomas
Reference 88491
Record set Wiltshire Memorial Inscription Index
Category Birth, Marriage, Death & Parish Records
Subcategory Deaths & burials

Inexplicably her burial date of 1 Dec is 18 days before her death!  1 Jan?
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Yvonne stated clearly in her will signed in 1968 that it was her will and she was “the wife of henry Thomas Parker of Van Ruan Gorran St Austell in the County of Cornwall”.  But no record can be found in Britain and eksewhere of any marriage.
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Later: Cracked it!

Their marriage index:

First name(s) WINIFRED Y
Last name LAUDON
Marriage quarter 3
Marriage year 1963
Registration month -
MarriageFinder™ WINIFRED Y LAUDON married
HENRY T PARKER
Spouse's last name PARKER
District PORTSMOUTH
County Hampshire
Country England
Volume 6B
Page 1325
Record set England & Wales marriages 1837-2008
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