Hi Andrea,
Sorry it has taken me a little while to come back - I had to find the census details reference numbers!! Located them at the bottom of the page - always something new to learn!!
1881 - Reg: 11/138 5 3 -

1891 - Reg: 12/92 19 31 - same as you
1901 - Reg: 13/106 13 17
1891 & 1901 are correct as my grt grandmother is born and living with her in both these censuses along with her sister.
I am hoping the 1881 is her, as 12 Little Marylebone St, is just to close to where he soon to be husband is living in 1881 at 2 Little Marylebone St.
The marriage certificate details are as follows:
Date: 7 Sep 1881
Husband: Alfred George Baker Elliott
Age: 29 years
Condition: Bachelor
Rank or Profession: Butcher
Residence: 2 Little Marylebone St
Fathers name: Alfred John Elliott - Bookbinder
Wife: Ellen Annie King
Age: 21 years
Condition: Spinster
Residence: 17 Nottingham Place
Fathers name: Edward King - Deceased - General Dealer
Married in the Register Office by Licence before Frank Stokes register and Joseph Bedford - Superintendent Registrar
Witnesses: Elizabeth Poulter & Tho Ansell
I have been unable to locate a will for Alfred, however, I will follow this up. My mum's cousin is quite definite that Ellen did not remarry, and that she died in 1929.
Any help would be terrific.
Many thanks
Jayne