Hi Yokel
On the 1891 census 
Mary A Brown head wid 46                         Suffolk Gorleston
Albert E   "     son u/m 18 blacksmiths lab      "           "
Ellen A Moss sister u/m 38                             "            "
Carnell W Thetford lodger u/m 33 plumber?painter Norfolk Norwich
living at 218 High Street, Gorleston, Suffol
Rg12/ 1496
folio 98
page 5
Any chance this being the right Mary Ann Brown from your 1881/1871 census, as there is a sister living with them. Also ther is a marriage for a Mary Ann Moss in 1864 and on the same page is a Jacob Brown.
 
On the 1861 census there is this family
Robert Moss head mar 63 farm lab  Norfolk Blofield?
Ann         "     wife mar 52                      "     Yarmouth
Robert     "     son u/m 22 farm lab     Suffolk Hopton?
Mary Ann  "    dau u/m 18 dressmaker   "       Bradwell
Ellen         "    dau u/m 11  scholar          "            "
living at Gorleston,Mutford,  Suffolk
Rg9/ 1198
folio 83
page 45
Ther is a Jacob Brown on the 1851 census aged 7 born Gorleston
Bit of a long shot but might be worth looking into
ricky