Question: Vladimir Olgerdovich was a son of which ruler of medieval Lithuania?

full_context: Document 1: Lithuanian Civil War (1389–92): The Lithuanian Civil War of 1389–92 was the second civil conflict between Jogaila, King of Poland and Grand Duke of Lithuania, and his cousin Vytautas. At issue was control of the Grand Duchy of Lithuania, then the largest state in Europe. Jogaila had been crowned King of Poland in 1386; he installed his brother Skirgaila as ruler of Lithuania. Skirgaila proved unpopular and Vytautas attempted to depose him. When his first attempt to take the capital city of Vilnius failed, Vytautas forged an alliance with the Teutonic Knights, their common enemy – just as both cousins had done during the Lithuanian Civil War between 1381 and 1384. Vytautas and the Knights unsuccessfully besieged Vilnius in 1390. Over the next two years it became clear that neither side could achieve a quick victory, and Jogaila proposed a compromise: Vytautas would become Grand Duke and Jogaila would remain Superior Duke. This proposal was formalized in the Ostrów Agreement of 1392, and Vytautas turned against the Knights. He went on to reign as Grand Duke of Lithuania for 38 years, and the cousins remained at peace.
Document 2: Vladimir Olgerdovich: Vladimir Olgerdovich (Belarusian: Уладзімер Альгердавіч , Lithuanian: "Vladimiras Algirdaitis" , Polish: "Włodzimierz Olgierdowic" , Ukrainian: Володимир Ольгердович ; died after 1398) was a son of Algirdas, Grand Duke of Lithuania, and his first wife Maria of Vitebsk. He was Grand Prince of Kiev from 1362 to 1394. His sons Ivan and Alexander started the Belsky and Olelkovich families.
Document 3: Family of Gediminas: The family of Gediminas is a group of family members of Gediminas, Grand Duke of Lithuania (ca. 1275–1341), who interacted in the 14th century. The family included the siblings, children, and grandchildren of the Grand Duke and played the pivotal role in the history of Lithuania for the period as the Lithuanian nobility had not yet acquired its influence. Gediminas was also the forefather of the Gediminid dynasty, which ruled the Grand Duchy of Lithuania from 1310s or 1280s to 1572.
Document 4: 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.
Document 5: Lithuanian Civil War (1381–84): The Lithuanian Civil War of 1381–1384 was the first struggle for power between the cousins Jogaila, Grand Duke of Lithuania and later King of Poland, and Vytautas the Great. It began after Jogaila signed the Treaty of Dovydiškės with the Teutonic Knights which was aimed against his uncle Kęstutis, father of Vytautas. Kęstutis briefly seized power in the Grand Duchy, but was betrayed by adherents of Jogaila primarily from Vilnius. During negotiations for a truce Kęstutis and Vytautas were arrested and transported to the Kreva Castle. Kęstutis died there a week later but Vytautas managed to escape and then sought an alliance with the Teutonic Knights. Subsequently their joint forces raided Lithuanian lands. Eventually the cousins were reconciled as Jogaila needed internal stability in anticipation of negotiations with the Grand Duchy of Moscow and the Kingdom of Poland regarding the possible Christianization of Lithuania. The war did not settle the power struggle; it continued during the next Lithuanian Civil War (1389–1392) which was resolved by the signing of the Ostrów Agreement. After more than ten years of struggle, Vytautas finally became the Grand Duke of Lithuania and ruled the country for thirty-eight years.
Document 6: History of Lithuania: The history of Lithuania dates back to settlements founded many thousands of years ago , but the first written record of the name for the country dates back to 1009 AD. Lithuanians, one of the Baltic peoples, later conquered neighboring lands and established the Grand Duchy of Lithuania in the 13th century (and also a short-lived Kingdom of Lithuania). The Grand Duchy was a successful and lasting warrior state. It remained fiercely independent and was one of the last areas of Europe to adopt Christianity (beginning in the 14th century). A formidable power, it became the largest state in Europe in the 15th century through the conquest of large groups of East Slavs who resided in Ruthenia. In 1385, the Grand Duchy formed a dynastic union with Poland through the Union of Krewo. Later, the Union of Lublin (1569) created the Polish–Lithuanian Commonwealth that lasted until 1795, when the last of the Partitions of Poland erased both Lithuania and Poland from the political map. Afterward, the Lithuanians lived under the rule of the Russian Empire until the 20th century.
Document 7: Vytautas: Vytautas (c. 1350 – October 27, 1430), also known as Vytautas the Great (Lithuanian: "   ", Belarusian: "Вітаўт Кейстутавіч (Vitaŭt Kiejstutavič)" , Polish: "Witold Kiejstutowicz" , Rusyn: "Vitovt", Latin: "Alexander Vitoldus") from the 15th century onwards, was a ruler of the Grand Duchy of Lithuania, which chiefly encompassed the Lithuanians and Ruthenians. He was also the Prince of Hrodna (1370–1382), Prince of Lutsk (1387~1389), and the postulated king of the Hussites.
Document 8: History of Lithuania (1219–95): The history of Lithuania between 1219 and 1295 concerns the establishment and early history of the first Lithuanian state, the Grand Duchy of Lithuania. The beginning of the 13th century marks the end of the prehistory of Lithuania. From this point on the history of Lithuania is recorded in chronicles, treaties, and other written documents. In 1219, 21 Lithuanian dukes signed a peace treaty with Galicia–Volhynia. This event is widely accepted as the first proof that the Baltic tribes were uniting and consolidating. Despite continuous warfare with two Christian orders, the Livonian Order and the Teutonic Knights, the Grand Duchy of Lithuania was established and gained some control over the lands of Black Ruthenia, Polatsk, Minsk, and other territories east of modern-day Lithuania that had become weak and vulnerable after the collapse of Kievan Rus'.
Document 9: Belsky family (Gediminid): The Belsky or Belski family (Russian: Бельский; plural: Бельские ) was a princely family of Gediminid origin in the Grand Duchy of Lithuania. It later deflected to the Grand Duchy of Moscow and played a key role during the regency of Ivan IV of Russia. The family started with Ivan Vladimirovich, son of Vladimir Olgerdovich and grandson of Algirdas, and ended with Ivan Dmitrievich Belsky in 1571. The Belsky name was derived from their principal possession of Bely, Tver Oblast.
Document 10: Kęstutis: Kęstutis (] ; born ca. 1297, died on 3 August or 15 August 1382 in Kreva) was a ruler of medieval Lithuania. He was the Duke of Trakai and governed the Grand Duchy of Lithuania, 1342–82, together with his brother Algirdas (until 1377), and with his nephew Jogaila (until 1381). He ruled over the Lithuanians and Ruthenians.
Document 11: Vladimir of Duklja: Vladimir (; died 1118) was the Prince of Duklja from 1103 to 1113. He was a son of Vladimir, the oldest son of earlier King Mihailo I of Duklja (r. 1050-1081), and thus a nephew of Constantine Bodin (r. 1081-1101). He married a daughter of Vukan, the Grand Prince of Serbia (in Raška), thereby ending the civil war between the two polities of Duklja and Raška, with a peace lasting 12 years. Vladimir had been appointed the rule of Duklja by his father-in-law, Vukan, after the death of his uncle, former King Kočopar, in Zahumlje. He was poisoned in 1118 on the orders of Queen Jaquinta, the widow of his uncle, Constantine Bodin. Jaquinta soon appointed her son, George, to the throne.
Document 12: 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.
Document 13: Andrei of Polotsk: Andrei of Polotsk (Belarusian: Андрэй Альгердавіч , Lithuanian: "Andrius Algirdaitis" Polish: "Andrzej Olgierdowic" , ca. 1325 – 12 August 1399, in the Battle of the Vorskla River) was the eldest son of Algirdas, Grand Duke of Lithuania, and his first wife Maria of Vitebsk. He was Duke of Pskov (through his deputy Yuri, 1342–1348) and Polotsk (1342–1387). As the eldest son of the Grand Duke, Andrei claimed his right to the throne after his father's death in 1377. Algirdas left Jogaila, his eldest son with his second wife Uliana of Tver, as the rightful heir. Andrei's rivalry with Jogaila, Grand Duke of Lithuania and later King of Poland, eventually led to his demise.
Document 14: Grand Duke of Vladimir: The Grand Duke of Vladimir was a prince during the Kievan Rus' and after its collapse. He ruled territory approximately bounded by the Volga, Oka and Northern Dvina rivers. Its capital was Vladimir during 1157-1238. Vladimir city was founded by a Kievan prince Vladimir Monomakh in 1108 and was destroyed by a Mongol invasion in 1238. The second important city was Suzdal', also destroyed by Mongols. The Grand Duke ("Velikii Kniaz", Great Prince) Yuri Dolgorukii (Yuri "Long-arms"), the seventh son of Vladimir Monomakh, began the lineage of Suzdal' and Vladimir-Suzdal' great princes. Vladimir-Suzdal' began the next consolidation of Russian lands, completed by Muscovy, which grew from within Vladimir-Suzdal.
Document 15: Vsevolod II of Kiev: Vsevolod II Olgovich (Cyrillic: Всеволод II Ольгович) (died August 1, 1146) was the Prince (Knyaz) of Chernigov (1127–1139) and Grand Prince (Velikiy Knyaz) of Kiev (1139–1146), son of Oleg Svyatoslavich, Prince of Chernigov.
ground_truth: Algirdas