Question: Who is Frederick Iv, Duke Of Holstein-Gottorp's maternal grandmother?
Sentence (from "Gülbahar Hatun (wife of Mehmed II)"): Gülbahar Hatun( 1432 – 1492) was the consort of Sultan Mehmed II, and mother of Sultan Bayezid II of the Ottoman Empire and the grandmother of Selim I.
Relevant evidence: No