Listed in the 1841 census for Central, South and East Oxfordshire as living at Deddington with his wife Sophia and three children:
Edward KNIBBS 30
Sophia 28
Mary Ann 7
Ellen 2
Harriet 7 weeks

Also living with them at that time were Francis KNIBBS, Edward's younger brother, and Hannah KNIBBS who is almost certainly Edward's mother, Susannah who was widowed in 1826.
__________

It is quite possible that the baby Emma who was buried at Deddington on 5th July 1849, aged 4 months, was another daughter of Edward and Sophia.
__________

Listed in the 1851 census as living in Hopcrafts Yard (off New Street), Deddington, Oxfordshire, England with his wife Sophia and four daughters:
Deddington, Hopcrafts Yard:
Edward KNIBBS 43 Groom Deddington
Sophia 38 Northamptonshire, Kings Sutton
Mary Ann 17 Deddington
Harriet 10 Deddington
Sarah 8 Deddington
Eliza 4 Deddington
No mention of the other daughter Ellen bap 1839
__________

Listed in the 1861 census for Oxfordshire and North Berkshire as living at Lime House Court, New Street, Deddington with his daughter:
Edward KNIBBS 1811 Deddington Oxfordshire Head Deddington Oxfordshire
Eliza KNIBBS 1847 Deddington Oxfordshire Daughter Deddington Oxfordshire

Clearly, this was after his wife Sophia had died and the other children had left home.
__________

Edward can be seen in 1871 census for Oxfordshire and North Berkshire, living at New Street, Deddington, Oxfordshire with his daughter Sarah Woods and her husband.
WOODS William 25 Ag Lab North Aston
WOODS Sarah 27 Wife Deddington
KNIBBS Edward 64 Father in Law Deddington

It's quite probably that it is his daughter Elizabeth, age 21 years, also living at Deddington but not at the same house as her father Edward:
KNIBBS Elizabeth 21 RG10/ 1447/ 4 Deddington
__________

Edward is listed in the 1881 census living at School Lane, Deddington, Oxfordshire, England
Edward KNIBBS Head W Male 73 Deddington, Oxford, England Gardner (Jobbing) (ND)

He is also listed in the 1891 Census as 82 years old, a widower, living at Back Lane, Deddington, and "Kept by the Parish".
__________

Edward is listed in the 1891 census living at Back Lane, Deddington, Oxfordshire, England. He was a widower and "Kept by the Parish".
__________

Edward died aged 85 years.

Mary can be seen at the 1861 census return living at Fenny Strattford Road, Stoke Hammond, Bedfordshire:
Mary A Knibbs Servant UnM 27 Domestic Cook Stoke Oxon Deddington

Ellen is a bit of a mystery. Her baptism is clearly shown at Deddington in 1839, but for some reason, she is not included in the census details for 1841.

I'm not completely sure this Emma was the daughter of Edward and Sophia. I note that they had another daughter named Emma who died in February, shortly before this Emma was born. I am assuming that this Emma was named after her. It is sad that she too died at just 4 months of age.