My great grandfather, legal name Adolph Irving Margolis, was from Kudirkos Naumiestis (then called Wladyslavovo) or Naishtot in Yiddish (Russian Occupied Suwalki province). However, I believe he was born, as well as his father and grandfather, in Utena, Lithuania. He immigrated to the New York in 1912 at the age of 14 or 15 (born in 1897/8). His Hebrew Name was Avraham Yitzchak, in Yiddish Abram Itsik. He had an older sister Ester Etlia, two twin younger sisters Rachel and Rivka, and a younger brother Chaim. His father was Shabtai Zalman (legal name Simon) and his mother Chaya (legal name Hannah) Schwartzman. His mother had at least one brother Levi Schwartzman who immigrated to Syracuse, NY and with which my great grandfather stayed with for a year or two upon immigrating himself as a child.
Adolph's paternal grandfather was Shmuel Tsvi Margolis, and his paternal great grandfather was Movsha/Moshe Margolis. His paternal uncle was Harry/Girsh Margolis, who moved to Cleveland and established a family of his own. My great grandfather married Esther Eva Horowitz in 1918 in New York City. Esther's parents were Samuel Horowitz and Anna Margolis. Samuel Horowitz was from Belarus, and Anna Horowitz (nee Margolis) was from Vilna. Samuel's parents were Israel Horowitz and Pearl Beuraes. Either Samuel or Anna were first cousins with Adolph's father, as Adolph and his wife Esther were second cousins. So they would share the same grandfather, Movsha Margolis.
We are also Leviim/Levites, so perhaps that helps in narrowing down the family line among Margolis' who are also Levites. And as the lore is that Margolis' are descendants of Rashi's daughters, perhaps if there was a known Levite who married one of Rashi's descendants and took the last name Margolis as an honorific, that could be something.
https://www.ancestry.com/discoveryui-content/view/286920:1369
https://www.ancestry.com/discoveryui-content/view/3203:1448
https://www.familysearch.org/ark:/61903/1:1:2WGF-8HF
