Research Notes:
Keats-Rohan states, [1]
Ricardus De Redvers
Norman, from Reviers, Calvados, arr. Caen, cant. Creully; held a single identifiable manor in Domesday Book, in Dorset. After the accession of Henry I he was given the honour of Plympton, a collection of former Domesday tenancies-in-chief that was to become the earldom of Devon in the time of Richard's son Baldwin (Sanders, 137). Apparently son of Baldwin, a brother of Richard de Redvers who d. c. 1050; these brothers were the sons of an unknown father, perhaps Hugh de Vernon, and the daughter of Fulk fitz Osmund, whose mother Satselina was a niece of the Norman duchess Gunnor, according to Robert de Torigny (discussed in Keats-Rohan, 'Aspects of Robert of Torigny's genealogies revisited', Nottingham Medieval Studies 37 (1993); R. Bearman, Redvers Charters, Introduction). By his wife Adleisa, daughter of William I Peverel of Nottingham, he had issue Baldwin, Robert de Sainte-Mère-Eglise, Hugh de Vernon, William de Vernon and Hawise, later wife of William I de Roumare, earl of Lincoln. He died in 1107, when his successor Baldwin was still a minor.
[1] K. S. B. Keats-Rohan, Domesday People, A Prosopography of persons occurring in English documents, 1066-1166 (Boydell & Brewer Ltd, 1999), 360, [GoogleBooks].