William de Grandison, Knight
was born at of Cassington, Oxfordshire, England Abt 1255/64.
His parents were Pierre I Sire de Grandson and Agnes de Neuchatel.
He married Sybil Tregoz Abt 1285/86
at of Donyatt, Somersetshire, England
was born at Ewyas, Herefordshire, England 1271
daughter of John de Tregoz, Lord and Mabel Fitzwarin
They were the parents of 5
Piers (Peter) de Grandison, Baron Grandison
born Abt 1289.
Mabilia de Grandison
born Abt 1294.
Katherine de Grandison
born Abt 1304.
William de Grandison, Knight died 27 Jun 1335 .
Sybil Tregoz died 12 Oct 1334 .