William de Tregoz
William was born about 1140 in Billingford, Norfolk, England.  He died after 1168.

 Agnes
Agnes was born about 1150.  She died after 1198.

 Robert I de Tregoz , Sheriff of Wiltshire
Robert I was born in 1168 in Salisbury, Wiltshire, England.  He died at the age of 47 in 1215 in Ewyas Harold, Herefordshire, England.