Hi Karen,
Thank you for your response. Here's the full entry from the 1851 census:
ref HO107 1631h folio 704 page 5: 16, Middle Street, Deal
John Bayley head un age 31 mariner born Deal
Isaac do brother un age 21 mariner born do
Hannah do sister un age 19 housekeeper born do
Sarah Bushell visitor un age 27 stay maker born Deal
So John was married sometime after the 1851 census was taken, as it still shows him as unmarried.
The closest that I could get to this family in 1841 has a John and a Hannah, but no Isaac. I've checked all Deal 1841, but can't seem to spot an Isaac Bayley aged about 11.
ref HO107 466-02 folio 70 page 37: Middle Street, Deal
William Bayley age 40 mariner
Sarah do age 40
John do age 20 j shoe m
William do age 15
Catherine do age 11
Hannah do age 8
all born in county
(This may or may not be the right family, have you got the marriage certificate for John and Hannah, which should give you Johns fathers name and occupation?)
Hope this helps a bit,
xx Carol