Question: Who is the paternal grandmother of Blanche Of Lancaster?
Sentence (from "Henry of Grosmont, 1st Duke of Lancaster"): Henry of Grosmont, 1st Duke of Lancaster, 4th Earl of Leicester and Lancaster, Earl of Derby (– 23 March 1361), of Bolingbroke Castle in Lincolnshire, was a member of the English royal family and a prominent English diplomat, politician, and soldier.
Relevant evidence: No