John is a witness to several charters of William (II), Earl Ferrers. In one of them he is described as "avunculus comitis", maternal uncle of the earl. This confirms him as a brother of Sibilla and hence a son of William and Bertha.
(BM Egerton Cht. 436)

This John is a possible candidate for the father of John de Knill. The Knill family have claimed that John de Knill, the founder of their family was a son of a John de Braose but it is not clear which John this could be. The Knill arms are a variant of the de Braose arms: gules, crusily fitchy, a lion rampant or. (right)

Father: William de Braose, Sheriff of Herefordshire

Mother: Bertha de Pîtres