Would like to add that there seems to be a doubt about a child named WILLIAM.
There is not a record that i can see of his birth [IGI, freebmd,] or death.
However, the one named ALBANY fits the time scale and has records.
As his wife predeceased JOHN BIBBY, and we do not have details of her death certificate regarding children to clarify things, I am thinking the informant for JOHN BILBY was not sure of the child's name who died before the voyage to Australia and said Will. instead of ALBANY.
Perhaps this informant was one of the other younger offspring.
Thoughts anyway.
There is a birth on IGI for Albany 7/2/1852 and his Christening.
The other children shown to the couple are as you have Louisa, Charles, George. Do not see Hannah.
Sue