A post on soc.genealogy.medieval shows Agnes as the daughter of John de Depden and Elizabeth Waleys. It references an article is the NEHGS Register Vol.120, pages 170-174. Another site mentions this same article, quoting ". . ."perhaps daughter and heir of Sir John de Depden by Elizabeth, daughter and heiress of Stephen Waleys of Burg Waleys."
I am wondering if there is any basis or supporting evidence for Agnes to be of the Depden family. I don't have access to the NEHGS Register.