Sir William Clopton

The IPMs of his stepfather Thomas de Crewe state William de Clopton, knight , is son and next heir of Gillian and John Clopton, aged 36 years and more [b. abt. 1382].

His IPMs give three different death dates: 7 September 1419, 5 October 1419 and 7 October 1419. Thomas his son and heir was aged 13 years and more.

“198. Joan, late wife of William Clopton, knt., appoints an attorney to deliver seisin to John Throckmorton, Esq., of her lands in Hull and More next Pershore. Dated at Hull 6 April 6 Henry VI [1428]. She also granted to Throckmorton Meade in Hull and More, which she had of the…”
"Selby, W. D. (1994) The Genealogist. New York: The Association for the Promotion of Scholarship in Genealogy. Snippet Available at: Google Books.

Throckmorton, C. W. (1930). Besford Excursus. In A Genealogical and Historical Account of the Throckmorton Family In England and the United States, with Brief Notes on Some of the Allied Families (pp. 42–43). Old Dominion Press. Archive.org.

Two sources contain different articles by the same author. Extracted pages are in Sources.
Steele, F. M. (1903) “Later Anchoresses of England,” in Anchoresses of the West. London: Sands & Co., pp. 101–102. Available at: GoogleBooks.
Steele, F. M. (1904) “An English Anchoress,” in The Catholic World: A Monthly Magazine of General Literature and Science, October 1903 to March 1904. New York: The Paulist Fathers, p. 331-337. Available at: GoogleBooks.