1861: 17, Chesnut Street, Liverpool
John COLLINS, Head b1833 Ireland - Boot Maker Employing 1man 1boy
Ellen COLLINS, Wife b1836 Parkgate, Cheshire
Joseph COLLINS, Son b1858 Liverpool
John COLLINS, Son b1860 Birkenhead
John C GRADY, Boarder b1818 Ireland - Schoolmaster
~~~~~~~~
Piece: 2682
Folio: 103
Page: 33
I wondered about that one too - John's occupation given as a
Labourer on marriage 1859 both minors at marriage
Information on the Marriage Certificate for Genealogy Research
if it says "minor" or "under age" that means between the ages of
12 and 20 for a girl and
14-20 for a boy,
I can't place a John & Ellen with occupation Labourer on 1861c there's this one wrong occ. though

and it would mean son Thomas born before marriage 1859

1861 RG9; Piece: 3098; Folio: 101; Page: 33
John Collins 24 Ireland cotton spinner
Ellen Collins 21 Ireland
Thomas Collins 4 (1857) Blackburn
Anne Collins 2
Edit
Don't think the above is your John & Ellen as there's a marriage in Blackburn 1855 John Collins & Ellen Hagan names on same page

Haven't been able to find an Ellen Grady with father Andrew occ. Labourer on 1851 census either