Research Notes:
The Oxford DNB biography of William Pantulf states, [1]
In 1112 Pantulf and his wife, Lescelina, and sons Philip, Ivo, and Arnulf confirmed their gifts to St Evroult, and granted 60 marks in silver to the new church, which Pantulf did not live to see completed. He died on 16 April, probably in 1112, and was buried in the cloister at Noron, together with his wife, who died on 21 September. His eldest son, Philip, succeeded to his Norman estates, and his second son, Robert, to his English ones. …
Ivo Pantulf (b. before 1114, d. in or before 1176), probably Robert's son, succeeded him as baron of Wem. He attested a charter of Stone, Staffordshire, between 1130 and 1135 and a royal charter in December 1137 or 1138, and made grants to Shrewsbury and Combermere abbeys between 1141 and 1155. He appears in 1165 in the Black Book of the Exchequer and in the Staffordshire pipe rolls of 1167 and 1168/9. He made a grant to Haughmond Abbey in 1175/6. He had three sons with a first wife—Hugh, Hameline, and Brice—and two with Alice de Verdon—William and Norman. He was dead by 1176.
[1] Mary Bateson, revised by Frederick Suppe, "Pantulf, William (d. 1112?)," Oxford Dictionary of National Biography (Oxford University Press, 2004, online edition), [Oxford_Dictionary_National_Biography], [OxfordDNB(UM)].