There is a number of Gilbert De Clares in the succession the youngest was
born 1295 Tewkesbury, England and died at Bannochburn before having children,
thus ending the line. Although he was not a Sinclair/St Clair by name, he
was 1st cousin 4 times removed of Thomas Saintclare (as per my Family Tree
relationship Calculator) his uncle Thomas De Clare was the predessor of
Thomas Seyntclare (Saint Clare) line of Oxfordshire, England. So the De
Clare blood transends to that St. Clair line. I have numerous links to these
lines.
Marilyn K. Eddy Siperek
Great Valley, NY