Sources

1) Source: Chancery: Inquisitions Post Mortem, Series I, Richard II "He died on 20 August last. Elizabeth late the wife of Brian de Stapilton, the younger, knight, aged 28 years and more, and Sibyl wife of William de Ryther, knight, aged 25 years and more, are his sisters and heirs. The said William de Ryther and Sibyl have issue... He held the under-mentioned manor of Kelfeld jointly with Margery his wife, deceased, by gift and grant of William de Kyrkeby, chaplain, and Robert de Tyndale to William de Aldeburgh, knight, his father, deceased, for life, with successive remainders to him and the said Margery and the heirs of their bodies, and to the right heirs of the said William de Aldeburgh, his father." Date: 1392. External Link
https://www.british-history.ac.uk/inquis-post-mortem/vol16/pp433-455. Reference: C 136/69/2 (Data from direct source)
2) Source: The History of Parliament . External Link
http://www.historyofparliamentonline.org/volume/1386-1421/member/stapleton-sir-brian-1417. Reference: Stapleton, Sir Brian (d.1417), of Carlton, Yorks. (Questionable reliability of evidence)