A.D. 850–1850, to have descended from Hugh de Beaumont, 1st Earl of Bedford (born 1106).
[4] Joan had borne him no children and William separated from her two years before his death and went to live in London, leaving her in Devon.
It is thought the split was due to Joan having had an affair with the Cornish gentleman Henry Bodrugan.
[5] Certainly during this period of separation from her husband she gave birth to a son John "Bodrugan alias Beaumont" (died 1486)[6] who was later declared by royal letters patent a bastard.
The right heir to William, namely his younger brother Philip Beaumont (1432–1473), in order to counter his persistence obtained royal letters patent dated 1467 proclaiming the bastardy.