In the movie Goodfellas, a minor character is named “Jimmy Two-Times” because he always says things two times—for example, “I’m gonna get the papers (get the papers).”
I’ve thought of Jimmy a bunch lately as Finn’s clearly been enjoying his own lines—to the point that he’ll often immediately repeat them in a whisper. While recounting some anecdote he might say, “…so I told Magdalena, ‘I’m the dad!’ (‘I’m the dad!’)”
I don’t think he knows we hear it, and he just clearly enjoys mastering language, conversation, and social conventions. We’ll have to see how long it goes on. (Margot might say, “Probably forever, given the way you repeat jokes just to make sure I heard your cleverness.” ;-))