Sir John de Gras, lord of Studley - Ancestors of John le Gras

This source shows the family tree for this profile; John le Gras' father was John le Gras aka john Crassus of Gemeling, whose father was john Crassus of Beverly.
The Publications of the Thoresby Society, Volume 17
https://books.google.com/books?id=zmUKAQAAMAAJ&pg=PA164&lpg...
In this same passage is mentioned another pedigree, conflicting with both this profile and the above, which has John le Gras of Gemeling the son of John le Aleman of Great Studley, who is son of Walter and Cecilia Aleman. Walter is said to be the son of Richard le Aleman ("the German"), who had Another son William and a daughter Cecilia who married Simon Persona de Lynton. From the Gascoigne MSS, and above.