Hi Pooh Bear
Assuming we're on the right track with John Mitchell the docker in the 1901 Census, I've looked further and have found John, and his father Job Mitchell and mother Mary in every Census apart from 1851. Job came from Spalding in Lincolnshire and there is a marriage of Job Mitchell and Mary Hatchett in Mar Qtr 1867 Kensington 1a 182. If you would like the census images and those of Mary Hatchett and Mary Ann Goodwin that I've found then send me a PM with your e-mail address and I can send them to you.
What I've found is:
1901
RG13 p798 f 123 p37
12 Behind the High Street, Herne Bay, Kent
Job MITCHELL Head 62 General Lab Spalding Lincs
Mary MITCHELL Wife 64 Buntingford Herts
1891
RG12 p367 f 18 p29
27 Deacon Street, Newington
Job MITCHELL Head 52 Dairman Milk Employer Lincs Spalding
Mary MITCHELL Wife 54 Herts Bushingford
Job H MITCHELL Son 18 London
John MITCHELL Son 15 London
1881
RG11 p 441 f 101 p 25
Metro Howards Bldg
King Edwards Refuge, 19 Albert St
Whitechapel, Mile End New Town (MENT)
Job MITCHELL Head 41 Brewers Servant Shalldin Lincs
Mary MITCHELL Wife 44 Buntingford Herts
David MITCHELL Son 13 Scholar MENT London E
Job MITCHELL Son 8 Scholar MENT London E
John MITCHELL Son 5 MENT London E
1871
RG10 p515 f 69 p25
16 Albert Street, MENT, Tower Hamlets
Job MITCHELL Head 32 Drayman Lincolnshire Spalding
Mary MITCHELL Wife 33 Keeps a small shop Herts Buntingford
David MITCHELL Son 3 Middx MENT
Thos J MITCHELL Son 2 Middx MENT (doesn't appear in later censuses; probably died young)
Ebenezer ALLEN Lodger 20 Brewers Serv Huntingdonshire Fenstanton
1861
RG9 p2525 f 131 p28
Danesmoor Road
Northwingfield, Clay Lane, Derbyshire
In the house of
Mary A DURAY Head Widow 52 Housekeeper Nottingshire Brinsley
and family
Job MITCHELL Boarder 21 Excavator Lincs Not Known
and other boarders
1861
RG9 p91 f49 p4
8 St John's Villas
Hampstead
In the house of
Josesp Seagloss Head 37 Merchant Importer ?Barasia British Subject
and family
Mary HATCHETT Servant Unmarried 24 Cook Buntingford Herts
and four other servants
1841
HO107 p610 f12 p17
Spalding Common
Spalding Lincs
John MITCHELL 35 Ag Lab
Martha MITCHELL 30
Joseph MITCHELL 15
John MITCHELL 13
Samuel MITCHELL 12
Daniel MITCHELL 9
William MITCHELL 5
Job MITCHELL 3
Emma MITCHELL 6mths
all born in the county
1841
HO107 p443 f18 p1
Bray's Row, Buntington, Herts
William HATCHETT 35 Ag Lab
Mary HATCHETT 35
John HATCHETT 10
William HATCHETT 10
Mary HATCHETT 5
Thomas HATCHETT 3
Elizabeth HATCHETT 7mths
all born in the county
Kind regards
Gaie