Ystifyn ab Iorwerth

See Peter Bartrum, https://www.geni.com/documents/view?doc_id=6000000173393042978 (June 2, 2022; Anne Brannen, curator) Bartrum's notes give "Iarll Derbi," which is found in the maunuscript, but he adds "There was no Earl of Derby of this name. Some later MSS say "son to the Earl of Derby.'"

" No sources cite the ancestry of Ystifyn, but we suspect he was the son of Iorwerth ap Aldud ap Owain ap Edwin;"

Please see Darrell Wolcott: Pedigree of "Ednowain Bendew II"; http://www.ancientwalesstudies.org/id92.html, [#85] (Steven Ferry, November 6, 2017.)

Please see Darrell Wolcott: Pedigree of Cynddelw Gam of Ystrad Alun; http://www.ancientwalesstudies.org/id94.html; [#190] (Steven Ferry, November 28, 2017.)

Please see Darrell Wolcott: Edwin of Tegeingl and His Family - Aldud ap Owain of Tegeingl; http://www.ancientwalesstudies.org/id83.html. (Steven Ferry, June 18, 2020.)