You really aren't going to find ship records for this time - but Frank Fox is a definite clue - he's probably a brother or uncle to Minnie. I notice that her first children in the 1881 census were b. Walsall and in 1881 at 26 Lantarra St, Walsall, there is:
Frank Fox, 41, b. Alrewas, Cooper
Betsey, 37, b. Walsall
Frank, 15, b. ditto, Caster
Mary Ann, 13, ", Scholar
William, 10, ", "
Charlotte, 7, ", "
Elizabeth, 4, ", "
Maria, 1, ", "
You could also try tracking the address listed for her (if a full street address is given on the marriage certificate) through the censuses to see who else lived there.