Question: Who is Konrad Ii Of Masovia's paternal grandfather?
Sentence (from "Siemowit I of Masovia"): Siemowit I of Masovia  (c. 1224/28 – 23 June 1262), was a Polish prince member of the House of Piast, Duke of Czersk during 1247-1248, Duke of Masovia (except Dobrzyń) during 1248-1262, ruler over Sieradz during 1259-1260.
Relevant evidence: No