I do believe that in one of the bonus features from the Ariel's Beginning DVD (I personally chose to ignore that whole movie and think of it as a strange AU not properly connecting to the rest of the canon) that they actually state that Ariel and her sister's mother also came from a large family and was the eldest child.
Oh nice! I like that, definitely works. And yeah TLM 3 was just so...boring?? Like why bother to make the animation so nice if /nothing happens/? Not to mention contradicting stuff that had come before it







