Elizabeth and Edwin were married at St. Dunstan, Stepney, London, England

I believe from an article in The Era, a London Sunday newspaper, that Edwin was the landlord at a pub called the Prince Albert, 11 Coopers Row, Crutchedfriars, All Hallows Barking, London, from 1856-1860.

Prince Albert, 11 Coopers Row, Crutchedfriars, All Hallows, Barking, Tower, City of London
__________

Edwin appears in the 1871 census at Doiver Road, Northfleet, Gravesend, Kent:
Edwin Geo Knibbs Head 49 Retired Victualler Barton Oxon
Elizabeth Knibbs Wife 47 Stepney London
Maria Knibbs Dau 24 Bethnel Green London
George Knibbs Son 8 St George in the East London

Living with them was Edwin's niece Emily, the daughter of his brother George Edwin who died at Balaklava:
Emily Knibbs Niece 19 Plumstead Kent
__________

Edwin appears in the 1881 census as Edward G Knibbs, living at 1 Dover Road, Northfleet, Kent, England. He is listed as "No Occupation" so assumedly, he was relatively wealthy.
Edward G. KNIBBS Head M Male 59 Oxford, England No Occupation
Elizabeth KNIBBS Wife M Female 56 London Stepney , London, Middlesex, England
George KNIBBS Son U Male 18 London St Georges East , London, Middlesex, England Clerk
Ann ROBINSON Serv U Female 25 Northfleet, Kent, England Domestic Servant

Also living with them as a domestic servant was Ann Robinson, aged 25, from Northfleet, Kent.

Edwin is listed as having "No Occupation" in the 1881 census and given that the family had a domestic servant, I assume he had sufficient finances so that he didn't have to work.
__________

Edwin appears under the heading of "Private Residents" at Hartfield Villas, Dover Road, Northfleet, Kent in Kelly's 1882 Directory of Kent.
__________

Death details provided by Bob Knibbs. Edwin George supposedly died in North Aylesford which is just north of Maidstone in Kent, in 1884, aged 62 years.

Elizabeth's parents are believed to be William and Mary A Oman. They can be seen in 1841 living at Tower Hamlets, Wapping, London, England. Her mother was listed as a publican.
Ann Oman 40 Publican
William Oman 40
Mary Oman 16
Elizabeth Oman 15
Maria Oman 13
William Oman 9
Ellen Oman 4
__________

Elizabeth's parents can be seen at the 1861 census at Public House, Little Thames Street, Whitechapel, Middlesex, England. William was born in around 1802 in Buckinghamshire, England. He was identified as a Dock Master at the 1861 census. His wife was also born in about 1802 in Bermondsey, Surrey, England.
The following details appear in the 1861 census:
Name Relationship Condition Sex Age Profession Where Born
OMAN, William Head Married M 59 Dock Master Buckinghamshire
OMAN, Mary A Wife Married F 59 Bermondsey Surrey
KNIBBS, Marion Granddaughter F 14 Scholar Mile End Bermondsey Middlesex
MUNFORD, Ellen Granddaughter F 12 Scholar Aldgate Middlesex
CARR, Thomas Visitor Widower M 47 Master Mariner Lynn Norfolk
DALYLEITH, Ann Servant Unmarried F 59 Cook Limehouse Middlesex
SPACKMAN, Mary A Servant Unmarried F 18 House Servant Shalford Essex
RUSHWORTH, Maria Daughter F 35 Limehouse Middlesex

I believe that the Granddaughter given as Marion Knibbs age 14 is in fact Maria Knibbs, the daughter of Edwin George KNIBBS and his wife Elizabeth (Oman).
__________

Elizabeth can be seen at the 1881 census living at Perry Street, Northfleet, Kent with her son George:

Name Relationship Age Gender Birthplace
George Knibbs Head 28 Male Stepney, London
Elizabeth Knibbs Mother 67 Female Stepney, London
Elizabeth Warner Servant 27 Female Cannedon, Essex
Town: Perry Street, Ecc. Parish: All Saints, Civil Parish: Northfleet, County: Kent
Registration: Strood, Northfleet, 7
Source: PRO/National Archives Reference # RG12/650 Folio 60 Page 58
__________

Elizabeth appears in the 1901 census, aged 77, "Living on Own Means" at 84 Darnely Road, Gravesend, Kent, England with her daughter who was by then widowed, and two grandchildren:

Elizabeth KNIBBS, Wid, 77, Living on Own Means, London Stepney
Maria CARR, Wid, 54, Living on Own Means, London Bethnal Green
Lionel CARR, Grandson, 21, Joiner Carpenter, St Clements Danes Strand London
Winifred CARR, Granddaughter, 19, St Clements Danes Strand London

Living with them was Rachel E Simpkins, servant, 17 from Gravesend, Kent

Elizabeth was baptised at St. Botolph Church, Aldgate, London, England

George appears in the 1881 census living with his parents, and unmarried.

George also appears in the 1891 census, still unmarried and living with his mother at Perry Street, Northfleet, Kent.

It's quite possibly this George who's death is identified in FreeBMD. If so, then he died in September 1895 aged 32 years, in the Thanet District of Kent, England.