Hi @Lola5
Thanks for your reply.
It would seem the Rebecca Villette at age 63 in 1891 living in "Uppingham" (which would have been the district Gretton in Northamptonshire came under) is, I would say, the same Rebecca Villette at age 42 in Marylebone in 1871.
Aged 42 at the time of the 1871 Census would mean this Rebecca Villette was born in 1829 or in 1828 and was coming up for 43 at some time in 1871. Rebecca at age 63 in 1891, would mean she was born in 1828 - I am not sure what the likelihood is that there was more than one Rebecca Villette born in the same year. Also, this info you have provided saying that she was at Marylebone St John in 1871 fits perfectly with the fact that she is absent from her brother's house in Gretton, Northamptonshire on the 1871 Census where her son was present at the time of that particular census.
Yes, it seems Rebecca Villette spent the 1860s/early 1870s at least going in between Gretton and London - seems she did so twice at least. Funny that Polette and Rebecca's son William went to go and live with his uncle, Rebecca's brother John Hull.
According to another user in the original thread over at the Beginners forum, Polette Villette's father Charles Villette's occupation is stated as "labourer" on Polette's marriage certificate/record to Rebecca Hull.
I'm sure the birthplace for Rebecca Hull on the 1871 Census is supposed to say Northamptonshire as opposed to Northumberland (I can see why the error was made, as both have "North" in their names!).
Thanks for your help, @Lola5. And yes, I agree; Polette is a very strange name and unusual I think even in France (I've looked on Google) but it is certainly French sounding.
The Charles and Amy Villette you mention were certainly part of Polette's family, as both these people were witnesses at Polette's marriage to Rebecca Hull. But as you rightly point out, Charles may not have been his brother but another type of relative. In my opinion, it is most likely that it was his brother, as Polette's father was called Charles and so Charles Villette (husband of Amy) was possibly the elder son of Charles Villette (Polette's father) and was named after him for that reason?
Going back to Rebecca, I did find a death record for her in the early 1900s the other night, I've forgotten on which website, which was recorded in "Uppingham" district, so I assume she died in Gretton and not in Marylebone or any other place in London.
It seems to me that Polette left London to go back to France for some reason, and when he did, rather than stay in London alone, Rebecca went back to Northamptonshire (sometime after 1871). Her death is recorded as "Rebecca Villette", so I guess she didn't re-marry after Polette left her (was it socially acceptable to do so in the 19th century?)
Things seem to be slowly but surely coming together. You've helped clarify/reinforce one or two things, so thank you for your help.
And I agree with you, there are so many people on this site who are passionate about researching other people's families and many of them have been really kind to me in helping me so far. Yourself included.