Hi there, Emsworthy and Shanko

Happy new year to the both of you!
Thank you very much with your suggestions and answers to my previously posed question.
On one hand, things have become a little clearer regarding my g g great grandmother. On the other hand, things have now become a lot more cloudy!
I had thought that my g g great grandfather, Richard Fenton, was the one who was widowed. It now turns out to be his wife.
The little girl with Jane, Sarah, is down on the 1881 census as being 11, so I guess the 12 could be attributed to 12 months rather than years?
I also have another question - on my g great grandfather's birth certificate, his mother is down as Jane Elizabeth Fenton, formerly Vincent. It appears that her surname got lost in translation. However, my question is this: if a woman has married and been widowed before marrying once again and then having other children, is it her maiden name or her former married name that is contributed to the formerly part on the certificate? I am confused with my g g great grandmother, as if she is widowed as the 1871 census states, surely Vinson would be her married name rather than her maiden name? Or was it popular for women to revert back to their maiden names?
Many thanks for all you have done for me

Best wishes,
Sgt Tollers