I have encountered a muddle.
The book The Lineage and Ancestry of HRH Prince Charles, Prince of Wales, by Gerald Paget Vol. 2 page 441 says (what I quoted in my previous question):
"115460 Alice, daughter of Thomas Stonor, by Joan, natural daughter of William de la Pole, 1st Duke of Suffolk."
The book Kingsfords' Stonor Letters and Papers 1290-1483 by Charles Lethbridge Kingsford Vol. 1 page xx:
"Thomas Stonor married before 1416, Alice, daughter and heiress of Thomas Kirby."
The same book has Thomas' will, listing his wife Alice.
Unless Thomas married twice (and the Stonor Letters don't indicate that) it seems the Prince Charles book got it wrong.
So on to WikiTree profiles.
The profile For Thomas Stonor (Stonor-1) links to Alice (Kirkby) Drayton. Note descrepancy in spelling.
This Alice (Kirkby-123) says she is the daughter of John Kirkby. I think this is the wrong Alice.
On to Alice (Stonor) Forster (Stonor-5), whose mother, Alice (Kirkby) Drayton, is listed as uncertain. Again, I think this link is to the wrong Alice, the right one is certain.
Joan de la Pole's page (Pole-222) probably needs some adjustmenets as well.
I'm not certified for editing pre-1500 profiles and, at least at the moment, I don't plan to be.
