Hi Joanna,
The safest way to know would be to order one of the children's birth certs.
However, I see they have a child age 2 on the 1861 census, and she was from Manchester.
I can see a likely marriage:
September quarter 1858
Manchester 8d 269
Joseph Hopkins to possibly Elizabeth Drake
The 1841 has an Elizabeth Drake age 2 in Manchester as follows
HO107/577/19 12 18
Joseph Drake, 40, Cotton Spinner
Joseph , 7
Cornielus, 4
Elizabeth, 2