Greet my kinsman Herodion....
Romans 16:11 ESV

Since several Jews are mentioned in this chapter and not called “kinsman”, this Herodion is more closely related to Paul than being another Jew, just as with Andronicus and Junia. Paul says nothing else about this man.

Based on his name--derivatives of the name Herod were common among Herod’s descendants--it’s possible that he was a member of the family of Aristobulus mentioned in v10, but if that were the case, then the whole family would be Paul’s kinsmen. Since Paul only calls Herodion his kinsman, it seems unlikely that Herodion was part of that house, unless as a servant.