Sources

1) Source: English Baronies: a Study of Their Origin and Descent, 1086-1327. Reference: Page 6; Barony of Gloucester (Questionable reliability of evidence)
2) Source: The Ecclesiastical History of England and Normandy: Volume II "The earl had by his first wife five sons and four daughters, whose names are as follows : Robert de Belesme, Hugh de Montgomery, Roger the Poitevin, Philip, and Arnold ; Emma, a nun and abbess of Almenesches, the countess Matilda, wife of Robert, earl of Morton, Mabel, wife of Hugh de Chateauneuf, and Sybil, wife of Robert Fitz-Hamon. By his second wife he had only one son whose name is Everard, and who being brought up to learning, became attached to the courts of William and Henry, kings of England, as one of the royal chaplain"