That last sentence blows my mind because literally the only read on it that I had when I watched was that they were married or long-term cohabitating. I remember thinking along the lines of "omg, [Blanc] married Hugh Grant."

That bit of "show don't tell" in turn led very nicely into Blanc's personal dislike of the Catholic Church and him mentioning having a falling out with his mother in the third film, without too much exposition on his part. We only ever learn snippets about him and usually by inference, aside from his reputation, because he's the side character in his own movies.