Looks like you John was a bit of a "naughty boy" also

Marriage;
2 January 1849, Parish Church, St Pancras
John ASHLIN Jnr, Full Age, Bachelor, Carman, Father JOHN Ashlin, China Burner
Louisa Mary COOPER, Full Age, Spinster, Father JAMES Cooper, Painter
Witnesses, Charles Flayman?/Hannah Cooper
1851 Census
A John Ashlin age says he is a Mariner and born at Sea.
A Prisoner in Millbank Prison, Westminster, Middlesex
1861 Census
St Pancras
RG9/106/103/63
Harriett ASHLIN, 61, Head, W, Lodging Housekeeper
Lidia, 20, Daug, Unm****
JOHN, 36, Son, Mar, Carman (image I think is 34)
Louisa, 34, Wife, Mar
John, 10
Louisa, 1
***Lydia Ashlin
Mother: Harriet Ashlin
Father: John Ashlin
Baptism: 24 Jan 1841 - St Pancras Old St Pancras, England
Fathers Occp China Man
Looks like right Family as 1871 there is a large gap between John 1850 and Louisa 1860 that rosie posted the link to for you.
Cant find Louisa in 1851 though!