Olelko - that's a diminutive name for Aleksander. Olelko Vladimirovich was a son of Vladimir and grandson of Algirdas.
Vladimir - is a Christian name, after a Russian Orthodox saint, who lived in the 10th century.
Vladimir Olgerdovich (Vladimir son of Algirdas - in Slavic style, probably used in Russian sources) must have a pagan name as well, probably one of these: Butskus, or Narimantas, or Lubartas. Latin sources might use a pagan name, or double name pagan+christian. Unfortunately, we don't have those sources found yet. But the Vatican now opened its library, so maybe there will be more information found soon? I hope, I'm not the only one looking.
Some sons of Algirdas became politically active before they were baptized, so their pagan names are known, some - after they adopted Christian names, then they are mentioned in sources with their Christian names. Some are known with both names Pagan+Christian.
Foreign authors use translations of sources that are available to them, and not necessarily everything that's written about the person or the event. Historians make conclusions often not knowing the languages in which original chronicles were written, so they use translations or speculations of previous historians, depending what is available. Gediminid dynasty is surrounded by legends. Most original written sources are from enemy chronicles, who fought Lithuania, so facts are thickened with slander. Then there are centuries of various historical interpretations and speculations, many authors did not know all: Latin, German, old Turkish, Russian, Ruthenian, old Slavic, Ukrainian, Polish, and Lithuanian languages - this is how many languages a person needs to know to be able to read all original sources and understand names and geographic locations mentioned in them. Even reading just one text - names, geographical places, and events, described in the same language are confusing, as they are spelled using a different spelling for one and the same, so it might seem, that another person is mentioned where there is only one. Plus Dukes liked to "adopt" their most faithful vassals and allies, calling them "son" or "brother", so this adds to the confusion...
And now we have a recent "historical content". There are Russian and Belorusian historians, who use history as a political tool in order to wipe out other nations and rewrite their history. This has been done during USSR rule, and now there is a renewal in these activities. It requires knowledge and experience to recognize these political-agenda-saturated sources, some are very sophisticated, signed by professors, and published in hardcover books. And there is an ocean of articles that use this historical smear propaganda as their base for information. And of course, there are some very professional and respectful history researchers in Russia, who are now not popular and whose career is limited due to their unpopular views. Wikipedia is based on a mix of both, so it can't be 100% reliable.
Fortunately, we have DNA. I hope someone will fund research for the Gediminid dynasty's old burials and living descendants, who claim their lineage origins from the Gediminid dynasty. Plus many archives are open to the public, and many ancient scripts are available to read on the internet. It only requires time and knowledge of languages.
Do not worry. I will take my time and find the solution for the Gediminid family tree on GENI. Thanks for all the help and attention to this issue.
