Did you ever get this census info you requested? If not, I have the images of the entries for these families. There is not one for John and Martha together. They were still living with their respective parents in 1851. I have both.
Let me know where I can forward the images if you'd like them.
I am also researching these families and if you have any information at all, I would appreciate if you can fill in any of my gaps - especially any more info on William
Ford and his wife Ann (John's father) and John
Hillier and his wife Eliza (Martha's father).
Christine
Blythe