Warner's chronology places Catherine's birth before 16 June 1264, possibly as early as 1261, and her death on 4 September 1264. Those alternatives leave her either about three months or about three years old at death. Joan's birth in December 1264 or January 1265 raises a further question about how the pregnancies fit together. An earlier birth for Catherine is suggested, while the surviving dates remain uncertain.
Notable Point · 1:23:02-1:24:15
How uncertain birth dates affect Edward I's family chronology
Conflicting dates for Catherine and Joan show how historians test medieval family chronology while leaving uncertainty visible.