Whilst the marriage image of Annie Harris to George Alldred records her father as George Harris a "sailor" I personally believe she did not know who her actual birth father was. I may well be wrong but please consider the following. I will again start with the 1861 census below.
1861.
https://www.familysearch.org/ark:/61903/1:1:MWM9-V8Zbirths:
HARRIS, THOMAS GEORGE GRIFFITHS
GRO Reference: 1856 D Quarter in PORTSEA ISLAND Volume 02B Page 354
HARRIS, JOHN WILLIAM GRIFFITHS
GRO Reference: 1858 D Quarter in PORTSEA ISLAND Volume 02B Page 339
HARRIS, ANNE GRIFFITHS
GRO Reference: 1861 M Quarter in PORTSEA ISLAND Volume 02B Page 367
On this census Thomas Harris the father is aged 28. Believe he dies
HARRIS, THOMAS 33
GRO Reference: 1865 D Quarter in PORTSEA ISLAND Volume 02B Page 283
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Birth of daughter after 1861 census
HARRIS,
CLARA JANE GRIFFITHS
GRO Reference: 1863 D Quarter in PORTSEA ISLAND Volume 02B Page 420
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By the 1871 census mother Mary Ann has the surname Mansbridge.
Piece: 1132
Folio: 122
Page number: 29
Thos W (Whittaker) Mansbridge 37 Head
Mary Mansbridge 34 Wife
Thomas H Mansbridge 14 Son
Clara H Mansbridge 7 Daughter
Sarah Mansbridge 1 Daughter
MANSBRIDGE,
SARAH KATE GRIFFITHS
GRO Reference: 1869 S Quarter in PORTSEA ISLAND Volume 02B Page 403
Death of Thomas W Mansbridge
MANSBRIDGE, THOMAS WHITTAKER
38 (aged 37 on 1871 census)
GRO Reference: 1872 J Quarter in PORTSEA ISLAND Volume 02B Page 258
Birth of a daughter after 1871 census
MANSBRIDGE, ADA MARY ELIZABETH GRIFFITHS
GRO Reference: 1871 S Quarter in PORTSEA ISLAND Volume 02B Page 416
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1881 census Mary Ann has reverted back to surname Harris
https://www.familysearch.org/ark:/61903/1:1:Q274-FM3R-----------------------------
1891 census Mary Ann has reverted back to Mansbridge
https://www.familysearch.org/ark:/61903/1:1:43FW-WN2-------------------------
Odd birth but appears in 1891/1901 census
1901 census Mary Ann still with surname Mansbridge
https://www.familysearch.org/ark:/61903/1:1:XSXZ-QJGMANSBRIDGE, GEORGE ALFRED BLAKE - No mmn
GRO Reference: 1876 J Quarter in PORTSEA ISLAND Volume 02B Page 40
John
ADDED: Clara Jane Harris married William John Tout in dq 1885.
Wonder who she recorded her father as?