Sue, this could be the birth of the Sidney Edward Dawson DOB 21 Aug 1906, who died in Plymouth in Feb 1986:

England & Wales, FreeBMD Birth Index, 1837-1915
about Sydney Edward Dawson
Name: Sydney Edward Dawson
Date of Registration: Jul-Aug-Sep 1906
Registration district: West Derby
Inferred County: Lancashire
Volume: 8b
Page: 547

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England & Wales, FreeBMD Birth Index, 1837-1915
about Edith Mona Dawson
Name: Edith Mona Dawson
Date of Registration: Jul-Aug-Sep 1909
Registration district: West Derby
Inferred County: Lancashire
Volume: 8b
Page: 530

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1911
Lancashire, Everton, South Everton, district 10, image 606
46 Northcote St, Everton

Ancestry's transcription:

Name Age
Joseph Dawson 40
Edith Dawson 31
Joseph Dawson 9
David Dawson 7
Sydney Dawson 4
Mona Dawson 1

JD dock official (gateman) b Isle of Man
ED b IOM
children all b Liverpool
Married 10yrs, 4 children, all living

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Likely marriage:

Engl
England & Wales, FreeBMD Marriage Index: 1837-1915
about Joseph Frederick G Dawson
Name: Joseph Frederick G Dawson
Date of Registration: Jan-Feb-Mar 1901
Registration district: West Derby
Inferred County: Lancashire
Volume Number: 8b
Page Number: 532

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and & Wales, FreeBMD Marriage Index: 1837-1915
about Edith Mary Cubbon
Name: Edith Mary Cubbon
Date of Registration: Jan-Feb-Mar 1901
Registration district: West Derby
Inferred County: Lancashire
Volume Number: 8b
Page Number: 532

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1901
Lancashire, Everton, South Everton 24/5
7 Wentworth St

Name Age
Mary Filkin 62
Edgar G McKee 24
Joseph Dawson 29
Edith Dawson 21

JD+ED boarders, married, b IOM. JD dockgate man.

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