Update as promised on the link between the four ladies in that 1841 census at St Martins in the Field.

James and Mary Smith had many children including Mary born c1888, Hannah, c1889 and Charity, c1896 all of whom were baptised in Chislet.
James Palfrey married Hannah Smith at Herne on 14 March 1807. Following that he was a witness at the marriage of William Wanstall to Mary Smith (18/5/1807, Fordwich) The other witness was Hannah Smith (sic)

James and Hannah Palfrey had a daughter Charlotte baptised December 1820 at Reculver.
Charity Smith, Mary Wanstall (nee Smith) with her daughter Mary and Charlotte Palfrey are all together on that 1841 census return as in my previous posting.
Hope this makes sense, plus I think it adds more credibility to your William Wanstall being the one born in Fordwich in 1808.

Regards,
Tony