Now you really do have me confused - Until I looked at the 1851 image for myself I thought we were working in Suffolk, but it seems that everybody except James Newman was born Norfolk and living there too.
This is an exact match for age and county for Charles but location is a little off. I don't know whether it helps or not.
Little Snoring, Norfolk
Elizabeth Banyard 70 Yes
John 35 ShoeM Yes
Ann 35 Yes
William 8 Yes
Charles 7 Yes
Hannah 5 Yes
Susan 3 Yes
Louisa 2 Yes
Elizabeth 3 months Yes
HO107; Piece 771; Book: Civil Parish: Little Snoring; County: Norfolk; Enumeration District: 7A; Folio: 4; Page: 3
I'm sure you are aware of the User Submitted Entry on the IGI of the birth for Charles with parents Charles Banyard and Elizabeth Becket. I would suggest that you check the parish register to see if you can find an accurate entry for a baptism.
If you have the marriage certificate it should state whether Elizabeth was a widow or single, and her father's name should match her maiden name.
Yes I'm confused - I think I mean the marriage certificate for James and Louisa, presumably one of them is widowed.
Again found a user submitted entry for the marriage of Charles Banyard and Elizabeth Beckett 5 February 1833 Reymerston, Norfolk so it would seem to be the Reymerston Parish Registers that you should check also although the parish for there and East Dereham may well be the same.
I can't find any trace of Banyards in Reymerston, however in East Dereham there are quite a number, although no Charles born c1833, nor an Elizabeth. There are however, a couple of Charles who might well be widowed - one is a Horse Keeper, aged 30 living in American Square
Another, again 30 living in the same dwelling in Etling Green, as a Robert Banyard 27 a Farmer, Sarah 30, Robert 2 and Fletcher 1.
Yet another living Fairstead, Gressenhall, a 25 year old Baker and John Banyard 15 Baker's Ap.
It's the Elizabeth Newman 9 I'm trying to sort out,
on my grand fathers birth certificate his mother is down as Elizabeth Banyard, but on his brothers cert. she's down as Elizabeth Newman,
James Newman didn't marry Louisa-previously Beckett until 1849.
I think this is what is confusing me most - in all of this I haven't got it clear in my mind just who is your grandfather and his brothr? If he is Elizabeth's son who isn't yet in the picture then could it be Elizabeth Newman who married Banyard and then remarried to your great grandfather?
I think I'm just doing too much guessing here without facts. I seem to have given you all I have found.