This whole arc is character development for her tho.
And she very much is the MC of this story.
She is not the MC off the manga as a whole, but this storyline follows her and thus she is the MC of this particular story.
@Daiankokuten
Maybe they had a firstborn son who died and named their second son after the first. Chronologically it would not make sense that it is the same person. We will most likely get an explanation soon. I have read the raw and there aren't that many chapters left in the arc.
maybe everyone is confused why only Lilia keeps appearing, why is she the only one being discussed. If I answered it would only be a spoiler. But let me give you a hint, the title of Season 2 explains why the focus of the story is on Lilia