Vladimir Olgerdovich was a son of which ruler of medieval Lithuania?
Algirdas Algirdas (Belarusian: Альгерд , Russian: Ольгерд , Polish: "Olgierd" ;  1296  – May 1377) was a ruler of medieval Lithuania. He ruled the Lithuanians and Ruthenians from 1345 to 1377. With the help of his brother Kęstutis (who defended the western border of the Duchy) he created an empire stretching from the present Baltic states to the Black Sea and to within fifty miles of Moscow.
Sophia of Lithuania Sophia (1371–1453) was the only daughter of Vytautas the Great of Lithuania and his first wife, Anna. On 21 January 1391, while her father was engaged in the Lithuanian Civil War, she married Vasili I of Russia. She was the longest serving consort of Russia. After Vasili's death in 1425 she became regent for their ten-year-old son Vasili II. Her father supported Vasili's claim to the throne, which was disputed by his uncle, Yuri of Zvenigorod. Sophia was buried in the Ascension Convent; the sarcophagus was moved in 1929 to the Cathedral of the Archangel by Soviet authorities.