m. (1) Charler Burt, (2) John W Allen, (3) John Tyrrell; issue only by 2nd.

Her birth index:

First name(s) BERTHA GERTRUDE
Last name HARDING
Birth year 1890
Birth quarter 2
Registration month -
Mother's last name -
District DORCHESTER
County Dorset
Country England
Volume 5A
Page 334
Record set England & Wales births 1837-2006
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No obvious births found for her marriage with Charles Burt.  There are in fact, nine Burt - Harding births but none around Dorchester; Oxfordshire is the closest county.
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I wonder if this is a second marriage for her?  It may need the certificate purchased.

First name(s) BERTHA G
Last name BURT
Marriage quarter 3
Marriage year 1924
Registration month -
MarriageFinder™ BERTHA G BURT married
JOHN W ALLEN
Spouse's last name ALLEN
District WEYMOUTH
District number -
County Dorset
Country England
Volume 5A
Page 791
Record set England & Wales marriages 1837-2008

Not needed.  Yes!  Confirmation from the CWGC site (marvellous) for her 1st husband’s Death in Action.
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And a possible third marriage, as it looks like her second husband John W Allen had died:

First name(s) BERTHA G
Last name ALLEN
Marriage quarter 2
Marriage year 1932
Registration month -
MarriageFinder™ BERTHA G ALLEN married
JOHN TYRRELL
Spouse's last name TYRRELL
District WEYMOUTH
District number -
County Dorset
Country England
Volume 5A
Page 702
Record set England & Wales marriages 1837-2008
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And if the above was her marriage (certificate needed, ordered and now received), might this be her death, the birth date is the same as on the 1939 Register:

First name(s) BERTHA GERTRUDE
Last name TYRRELL
Gender Female
Birth day 19
Birth month 4
Birth year 1890
Age -
Death quarter 3
Death year 1986
District WEYMOUTH
Register number 786
County Dorset
Volume 23
Page 857
Country England
Record set England & Wales deaths 1837-2007
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Certainly the same lady was a Boarding House proprietoress in 1939, judging with her birth date:

Address: 2 Salisbury Villas , Dorchester M.B., Dorset

FIRST NAME(S) LAST NAME(S) DOB SEX OCCUPATION MARITAL STATUS  SCHEDULE  SCHEDULE SUB NUMBER

Bertha G Tyrrell 19 Apr 1890 Female Boarding House Proprietress  Married  308  1
[Sorry, this record is officially closed. Check if you can open a closed record.]
Vera ? Bennett (Fooley,Bennett) 05 Sep 1918 Female  Unpaid Domestic Dutie  Single  308  3
William Toogood 26 Sep 1887 Male Brewers Labourer Single  308  4

The redacted line on this report indicates a youngster (probably).  I wonder if it might be a child of hers, though she was 49 years old then and a few years past childbearing.  There is an Allen child on the birth indexes with a Harding mainden name, now confirmed by the birth certificate to be hers: Mabyn Nesla Allen.
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Their marriage index:

First name(s) BERTHA G
Last name HARDING
Marriage quarter 2
Marriage year 1914
Registration month -
MarriageFinder™ BERTHA G HARDING married
CHARLES BURT
Spouse's last name BURT
District DORCHESTER
District number -
County Dorset
Country England
Volume 5A
Page 808
Record set England & Wales marriages 1837-2008
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Their marriage index:

First name(s) BERTHA G
Last name BURT
Marriage quarter 3
Marriage year 1924
Registration month -
MarriageFinder™ BERTHA G BURT married
JOHN W ALLEN
Spouse's last name ALLEN
District WEYMOUTH
District number -
County Dorset
Country England
Volume 5A
Page 791
Record set England & Wales marriages 1837-2008
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Their Marriage Certificate:

Header
------
Year: 1932
Where: The Register Office, Weymouth, Dorset
Cert No: 42
Date: 7 Apr 1932

Details
-------
Groom Bride
----- -----
Name: John Tyrrell Bertha Gertrude Allen
Age: 57 41
Status: Widower Widow
Job: Auctioneer’s Porter -
Abode: 6 Crescent Street, Weymouth 6 Crescent Street, Weymouth
Father Thomas Tyrrell (deceased) Albert harding (deceased)
Father job: Shepherd Farmer

Witnesses: W. G. Cocks, V. M. Mitchell

Registrars:  C.H. Shear (Deputy), H. O. G. Stevens, (Superintendent)
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