Name: Walter de CAEN , Lord of Sibton 1 2 3 4
Birth: ABT 1044 in Caen, Calvados, Normandy, France
Death: AFT 1086 in Sibton, Blything, Suffolk, England
The following quotation from the "Butler Family History" indicates that Walter is son of William Malet, which would explain the age difference between Walter & William (ie. they weren't brothers as many old sources stated}:
Theobald Blake Butler, a leading authority on the history of the family, who died only this year  and whose works are now available to scholars in the National Library, Dublin, the British Museum and the Irish Genealogical Research Society, laboriously traced back to Domesday the lands which this family subsequently held in East Anglia and Lancashire and discovered that at least nine of the sixteen or more holdings which our Hervey was believed to have owned in Norfolk and Suffolk were entered in Domesday Book under the ownership of Walter de Caen. The discovery led him to surmise that the paternal ancestor of the Butlers was Walter de Caen (son of William Malet who accompanied the Conqueror and, being half Saxon, was entrusted with the burial of King Harold after the Battle of Hastings).
'The Domesday Book, England's Heritage, Then and Now' states that Walter de Caen was Lord of Sibton, given to him by Robert Malet's mother (William Malet's widow).
The following is part of a post to SGM, 17 Sep 1999, by Richard Borthwick, citing 'Domesday Descendants'.
I don't know whether this is the Walter de Caen under consideration but Keats-Rohan at I:449 has an entry for a Walter de Cadamo (de Caen). His father was Alberic. There is no mention of a wife but he had three sons: Robert (ancestor of the Chesney family), Ralph and Roger (ancestor of the Huntingfield family). Walter held Horsford, Norfolk, from Robert Malet with whom he came to England in 1066. Robert's wife was Sibil de Chesney dau. of Ralph (II) fitz Ralph (I). William, Robert's son, took his mother's name and was lord of Blythborough, Suffolk.
NOTE: Based on the Walter not being a brother of William Malet, the approximate birth dates, and the fact that 'Domesday Descendants' states that Walter's father was named Alberic, I am making Walter de Caen son of William Malet's wife, by an earlier husband, named Alberic. William's widow giving Walter the manor of Sibton would imply blood relationship. I believe that Walter was her son, making him a half-brother of William Malet's children.
Father: Alberic de CAEN b: ABT 1020 in Caen, Calvados, Normandy, France
Mother: Hesilia (Elise) CRISPIN b: ABT 1027 in Tillieres, Maine-et-Loire, Anjou/Pays-de-la-Loire, France
- Robert FITZWALTER , of Horsford b: ABT 1090 in Horsford, St. Faith's, Norfolk, England
- Reginald (Ralph\Nigel) de PEYTON b: ABT 1093 in Peyton Hall, Ramshold, Suffolk, England
- Roger de HUNTINGFIELD , Sir b: ABT 1095 in Huntingfield, Blything, Suffolk, England
- Daughter of Walter de CAEN b: ABT 1100 in Horsford, St. Faith's, Norfolk, England
- Title: The Plantagenet Ancestry, by William Henry Turton, 1968
Text: Walter (no name or ancestry) father of Robert FitzWalter who m. Sibyl de Chesney
- Title: The Domesday Book, England's Heritage, Then and Now, by Ed Thomas Hinde, London 1985
- Title: Butler Family History, 7th Edition 1991, by Lord Dunboyne, Kilkenny Castle Book Shop
- Title: Newsgroup: soc.genealogy.medieval, at groups - google.com
Page: Richard Borthwick, 17 Sep 1999