Noted events in his life were:
• Background Information. 141
Eustace married, 1st, Beatrice, only daughter and heir of Yves de Vescy, lord of Alnwick and Malton, by [it is said] "Alda" only daughter and heir of William Tyson, also lord of Alnwick and Malton. She died in childbirth.
~Cockayne's Complete Peerage, (Vescy), Vol. XIIB, pp. 272-274
• Background Information. 1417
The family of Tysons was not Saxon, and it did not hold the barony of Alnwick before the conquest. According to Doomsday Book, Malton barony, instead of being in the possecion of Yvo de Vescy, in the right of his wife, as heir of the Tysons, was in the hands of the king himself; and it was not until the early part of the twelfth century, that it becaame the property of the Lord of Alnwick by gift of King Henry I. Tyson indeed was a Norman family. Gislebert, father of William Tyson, followed William (the Conqueror) from Normandy, along with the Percys, de Vescys, and other adventurers.
"There is no authentic record of Gislebert having a son called William, and therefore the statement, often repeated*, that Alda, the daughter of this William, was given in marriage by William the Bastard to Yvo de Vescy in reward of his services, must be regarded as a myth."
* Dugdale, Baronage, Vol. I, p. 89: "Among the valiant Normans that assisted Duke William in his conquest of England were Robert and Yvo de Vesci. On Yvo, the conqueror bestoved the daughter and so heir of William Tyson, Lord of Alnewicke in Northumberland and of Malton in Yorkshire, two large baronies, both belonging to Gilbert Tyson, his father slain in battle on the part of King Harold."
~The History of the Borough, Castle, and Barony of Alnwick, Volume I, pp. 35, 45