Keats-Rohan states, [1]
Filius Haimonis, Robert
Son of Haimo dapifer, sheiriff of Kent (d.c. 1100). Identified as a grandson of Haimo Dentatus by William of Malmesbury: 'Hamonem dentatum avum Roberti qui nostro tempore in Anglia multarum possessionum incubatur extitit' (Gesta Regum RS ii, 386). A favourite of William II, who gave him the lands of Queen Matilda, which had been sought by the king's younger brother Henry. Benefactor of Caen, Sées, and Mont-Saint-Michel. In a charter for Sées (Arch. Orne H938, fol. 34) mention is made of his nephew Escirard, who should perhaps be identified with Escirard husband of Hildiardis de la Chapelle-Hamelin, near Saint-James, Manche, a benefactor of Mont-Saint-Michel (Bib. mun. Avranches MS 210, fols 70, 79v-80). The grants of Robert and his knights to Tewkesbury abbey were confirmed in 1109 (Mon. Ang. ii, 81; EEA xviii, 20). This was two years after Robert's death, which followed serious injuries sustained in 1105 (Ann. Mon. i, 44). By his wife Sibil, daughter of Roger de Montgomery, he was father of Mabel, wife of Robert earl of Gloucester, and possibly also of Cecilia abbess of Shaftesbury and Havise abbess of Wilton (cf. Mon. Ang. iv, 60).
[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), 902-903.