Question: Who is George Iii Dadiani's paternal grandfather?
Sentence (from "George III Dadiani"): Giorgi Dadiani's hold of power in Mingrelia, one of those states that had emerged after the disintegration of the Kingdom of Georgia in the 15th century, was challenged by the neighboring ruler, Giorgi Gurieli, Prince of Guria, and his own younger brother, Mamia IV.
Relevant evidence: No