The Bexfield/Rix/Rex are a "problem" family. On civil registrations they are BEXFIELD.
On the 1891 the family are RIX and again on the 1901 they is RIX. and as you already know on the 1881 census they are WEXFIELD
Have you got a Broadband connection? If you have I will send you the census images in large format if you have not I will compress them - Then you can check the occupants on the census against the BMD's and see that they are the right family.
There are many clues in genealogy, which after years you just "know" that you are on the right track. If you goto the 1881 census on Family Search and get Alice Emily - you find:
Robert R. WEXFIELDHeadMMale28Norwich, Norfolk, EnglandBricklayers Laborer Alice R. WEXFIELDWifeMFemale28London, Middlesex, EnglandDressmaker Alice E.R. WEXFIELDDaurFemale7Norwich, Norfolk, England Annie R. WEXFIELDDaurFemale2Norwich, Norfolk, England Fred R. WEXFIELDSonMale3 mNorwich, Norfolk, England
Compare the above with the 1891:
RIX, Robt Head Married M38 Yardman Norwich Norfolk. RIX, Alice Wif eMarried F37 Dressmaker Barnsley London. RIX, Alice Daughter Single F17 Brushmaker Norwich Norfolk. RIX, Annie Daughter F12 Week Girl Norwich Norfolk. RIX, Fredk SonM 10 Scholar Norwich Norfolk. RIX, Eliza Daughter F8 Scholar Norwich Norfolk. RIX, Chas Son M7 Scholar Norwich Norfolk. RIX, Jane Daughter F2 Norwich Norfolk.
Same family, different name - and also note the names which Alice continued with her children.