Apparently she and William Knyvett had a descendant of John Alured of Charterhouse, regice and thus yet another related such, though distantly.  Thanks to Brad Verity who wrote on 18 Apr 2007 on soc.gen.med:


Joan Beaufort, Countess of Westmorland (c.1379-1440), had a daughter
(A1)

A1) Anne Nevill, Duchess of Buckingham (c.1406-1480), who had
A2) Joan Stafford (1442-1484) m. 2)1477 Sir William Knyvett of
Buckenham, Norfolk (1440-1515), and had
A3) Charles Knyvett of Hamerton, Huntingdonshire (c.1478-by 1528) m.
Ann (?)Hugford, and had
A4) Lucy Knyvett (d. 1577) m. by 1544 Sir Henry Gates of Seamer,
Yorks. (by 1523-1589), and had
A5) Frances Gates (1552-aft.1592) m. c.1580 John Alured of the
Charterhouse, Hull (d. 1611), and had
A6) Henry Alured of the Charterhouse (1581-1628) m. Frances Vaughan
(d. 1626), and had
A7) John Alured of the Charterhouse, M.P., Colonel in the
parliamentary army, regicide (1607-1651)
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