William de Grandison, 1st Lord Grandison - Children of William de Grandison (d 1335)

In a switch from our usual problem, https://www.wikitree.com/wiki/Tregoz-3 shows more children & an additional wife for

William de Grandison, 1st Lord Grandison & Sibilla de Tregoz, co-heiress of Ewyas-Harold

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Easiest seen as:

https://www.wikitree.com/wiki/Tregoz-3

Sibyl Tregoz married William de Grandison, Knt., younger son, minor in 1263. They married before 1285.
Children of Sibyl de Tregoz with William de Grandison, Knt.

1. Peter De Grandison, Knt., 2nd Lord Grandison, son and heir. He married before 10 June 1330 Blanche De Mortimer. Sir Peter de Grandison, 2nd Lord Grandison, died 10 August 1358.
2. John De Grandison, Chaplain to Pope John XXII, Bishop of Exeter, born in 1292. John De Grandsion, Bishop of Exeter, died 16 July 1369.
3. William De Grandison, Archdeacon of Exeter.
4. Thomas De Grandison, clerk. He died at the Roman curia shortly before 4 August 1317.
5. Otes De Grandison, Knt. He married before 28 October 1340 Beatrice Malmains. They had three sons, Thomas, K.G. [4th Lord Grandison], Walter, and Peter, and one daughter, Elizabeth. Sir Otes De Grandison died 23 May 1359.
6. Edmund.

They had four daughters,

1. Agnes,
2. Mabel,
3. Maud [Prioress of Aconbury], and
4. Katherine.