Research Notes:
Keats-Rohan states, [1]
de Haia, Robert
Norman from La Haye-du-Puits, Manche. One of Henry I's new men. Given lands forfeited in Sussex by William de Ansleville, known as the honour of Halnaker. Acquired the Lincolnshire barony of Kolswein by marriage with his granddaughter Murial, daughter of Picot. (BL Add. 35296, fol. 413), by whom he had two sons, Richard and Ralph. Founder of Boxgrove priory in Sussex before 1105, when he called himself son of Ranulf the seneschal of Robert of Mortain and nephew of Eudo dapifer (son of Thurstin Haldup (Cart. Boxgrove no. 4 Gall. Christ. xi, Inst. 224ff)). He died c. 1150. The honor of Halnaker passed to Roger St. John in marriage with his daughter Cecelia, his principal heir in Lincolnshire was his son Richard. Sanders, 109.
[1] K. S. B. Keats-Rohan, Domesday Descendants, A Prosopography of persons occurring in English documents, 1066-1166: II Pipe Rolls to Cartae Baronum (Boydell Press, 2002), 496.