Hi Rozzi
Sorry for the late reply to your request.
1. Have you purchased the marriage cert for Henry William Payne & Sarah Jane Willis registration district St George in the East Dec 1/4 1881? They may not have married in that church, St Geo in the East is a registration district in its own right as well as a parish
http://homepages.gold.ac.uk/genuki/MDX/Stepney/outline.htmThe marriage cert will tell you who their reputed father's were and occupations.
You will also find out how literate they were, signing the register with their names or leaving a mark, X (although not a fool-proof method)
It is possible that Sarah may not have been able to read and her surname may have sounded like Willis to the vicar, it could have been something else and she didn't know how to spell.
2. Have you got or purchased a birth cert for James? The 1881 census says aged 10 months born Bermondsey which was in St Olave Southwark district, the nearest James I can find is James Charles Wells June 1/4 1880. If his parents weren't married at the time, the surname Payne might not have been put on the register. There is no cert entry for James Payne, that reg district in 1880.
By the 1891 census there are 5 more children, I can suggest birth cert entries for 4
Alice Emily Mar 1882
Sarah Ann Dec 1883
Benjamin John Dec 1885
Caroline Mary A Mar 1887
but Nellie could be Helen Mar 1888 or Ellen Elizabeth Dec 1888
All these were registered in St Olave Bermondsey district.
These should state their mother's maiden name.
Without confirmation of a surname and/or father's name for Sarah (Willis) by buying the marriage cert you most probably won't be able to progress much further with this line.
Hope this helps
Dawn