William de Albini, 3rd earl, who, in 1218, embarked in the Crusade and was at the celebrated siege of Damietta, but died in returning, anno 1221. He m. Maud, dau. and heiress of James de St. Hillary, and widow of Roger de Clare, Earl of Hertford, by whom he left issue, William and Hugh, successors to the earldom; Mabel, m. to Sir Robert de Tateshall; Isabel, m. to John FitzAlan, Baron of Clun and Oswestry; Nicola, m. to Roger de Somerie, Lord of Dudley; Cecilia, m. to Roger de Montalt; and Colet. [Sir Bernard Burke, Dormant, Abeyant, Forfeited, and Extinct Peerages, Burke's Peerage, Ltd., London, 1883, p. 3, Albini, Earls of Arundel]
NOTE: "His lordship left by Adeliza, his wife, widow of King Henry I, four sons and three daughters, the eldest of whom, Alice, m. John, Earl of Ewe. The eldest son, William de Albini, 2nd earl, had a grant from the crown, 23rd Henry II [1177-78], of the Earldom of Sussex, and in the 1st of Richard I [1189-90], had a confirmation from that prince of the castle and honour of Arundel, as also of the Tertium Denarium of the county of Sussex. He d. in 1196 and was s. by his son, William de Albini, 3rd earl...[who] m. Maud, dau. and heiress of James de St. Hillary." [Sir Bernard Burke, Dormant, Abeyant, Forfeited, and Extinct Peerages, Burke's Peerage, Ltd., London, 1883, p. 3, Albini, Earls of Arundel]
All other sources that I've found say that the William who m. Maud de St. Hillary was the son of William, the 1st Earl, and Adeliza. I have, thus, compressed this pedigree by omitting the intervening William who Burke styles 2nd earl.