The father has data to estimate with:
“He was heir to his uncle William de Bodrugan and was aged 30 and more in 1308 [b. abt. 1278] / 1263.”
“ Henry and Sybil had two children:
These children and their spouses feature heavily in the novel The House on the Strand by Daphne du Maurier.
So now we know how to correct the daughter.
Good catch. I set Joan Bonville to blank birth date also.
There’s a primary source referenced in her profile, and the Tudor Place site has the line - to be used with caution, he compiled pedigrees from “various internet sources.”
http://www.tudorplace.com.ar/CHAMPERNOWNE.htm#Joan%20CHAMPERNOWNE1