1861 census RG9 640 folio 70
7 Witton Place Portsea Hampshire
Thomas Hancock 25 Portsea, Hampshire, Head Married Rope Makers Labourer
Maria Hancock 24 Portsea, Hampshire, Wife Married
Ann E Hancock 4 Portsea, Hampshire, Daughter
Thomas P Hancock 2 Portsea, Hampshire, Son
George W Hancock 1 Portsea, Hampshire, Son
1871 ensus RG10 1138 folio 69
8 Lord Street Portsea Hampshire
Thomas Hancock 35 Landport, Portsmouth Head Married Labourer Dockyard
Maria Hancock 34 Landport, Portsmouth Wife Married Staymaker
Thomas P Hancock 12 Landport, Portsmouth Son
Jane A Hancock 9 Landport, Portsmouth Daughter
Ellen L Hancock 8 Landport, Portsmouth Daughter
Emily M Hancock 4 Landport, Portsmouth Daughter
Julia E Hancock 3 Landport, Portsmouth Daughter
Fanny Hancock 9mths Landport, Portsmouth Daughter
You will need to check this 1851 census entry against the details Thomas junior gives on his marriage for his father.
1851 census HO107 1659 folio 376
Swanmore Place Portsea Hampshire
Thos Hancock 42 Portsea, Hampshire, Head Married Cabinet maker
Mary Hancock 35 Farlington, Hampshire, Wife Married
Thos Hancock 15 Landport, Hampshire, Son
Walter Hancock 2? or 12 Landport, Hampshire, Son
Harriett Hancock 5 Landport, Hampshire, Daughter
Henry Hancock 3 Landport, Hampshire, Son
Willm Hancock 11mths Landport, Hampshire, Son
James Smith 25 Landport, Hampshire, Wife's Brother Married Sawyer
Margaret Smith 25 Landport, Hampshire, Wife's Sister-in-law Married
HARRIET HANCOCK
Birth: 26 FEB 1845
Christening: 25 AUG 1850 Saint Marys, Portsea, Hampshire
Father: THOMAS HANCOCK
Mother: MARY
HENRY HANCOCK
Birth: 16 AUG 1847
Christening: 25 AUG 1850 Saint Marys, Portsea, Hampshire,
Father: THOMAS HANCOCK
Mother: MARY
WILLIAM HANCOCK
Christening: 25 AUG 1850 Saint Marys, Portsea, Hampshire
Father: THOMAS HANCOCK
Mother: MARY
a possible second marriage for Thomas but this would mean either James Smith was Mary's half brother or Mary was a widow on her marriage. If it is the correct marriage you will have the details of Thomas senior's father.
THOMAS HANCOCK
MARY FORD
Marriage: 12 MAY 1844 Saint Marys, Portsea, Hampshire
WALTER HANCOCK
Christening: 16 MAY 1841 Saint Marys, Portsea, Hampshire,
Father: THOMAS HANCOCK
Mother: JANE
THOMAS HANCOCK
Christening: 06 SEP 1835 Saint Marys, Portsea, Hampshire
Father: THOMAS HANCOCK
Mother: JANE
GEORGE HANCOCK
Christening: 18 AUG 1833 Saint Marys, Portsea, Hampshire
Father: THOMAS HANCOCK
Mother: JANE
THOMAS HANCOCK
JANE PARSONS
Marriage: 12 FEB 1832 Saint Thomas, Portsmouth, Hampshire
Not the easiest census entry to find
1841 census HO107 414/7 folio 34 page 23
Crasswell Street Portsea Town Hampshire
Thomas Hencoch 30 Hampshire Cabinet maker
Jane Hencoch 30 Hampshire
Thomas Hencoch 6 Hampshire
Wallter Hencoch 1mth Hampshire
Thomas senior's second marriage should help confirm the details of his father to be sure of the baptism entry
THOMAS HANCOCK
Birth: 21 MAY 1808
Christening: 20 NOV 1808 Saint John, Portsea, Hampshire
Father: THOMAS HANCOCK
Mother: ANN
possible siblings
GEORGE HANCOCK
Christening: 15 JUN 1800 Saint John, Portsea, Hampshire
Father: THOMAS HANCOCK
Mother: ANN
HARRIOT HANCOCK
Birth: 09 AUG 1805
Christening: 17 NOV 1805 Saint John, Portsea, Hampshire
Father: THOMAS HANCOCK
Mother: ANN
Regards
Valda