Question: Who is Isabella Of Gloucester And Hertford's paternal grandfather?
Sentence (from "Gilbert de Clare, 5th Earl of Gloucester"): Gilbert de Clare, 4th Earl of Hertford, 5th Earl of Gloucester, 1st Lord of Glamorgan, 7th Lord of Clare (1180 – 25 October 1230) was the son of Richard de Clare, 3rd Earl of Hertford (c. 1153–1217), from whom he inherited the Clare estates.
Relevant evidence: Yes