Question: What is the date of death of Siemowit Vi Of Płock's father?
Sentence (from "Siemowit VI of Płock"): Siemowit VI of Płock (pl: "Siemowit VI płocki"; 2 January 1446 - 31 December 1461/1 January 1462), was a Polish prince member of the House of Piast from the Masovian branch.
Relevant evidence: No