Luisa should have been the oldest sister because then the dynamic would've make more sense
Luisa- The oldest sister who has to take on everything the youngers can't take because well she's the oldest and is supposed to be the mature and strong one
Isabela- The middle striving to be perfect out of fear of being pushed behind and failing
Mirabel- The youngest who, compared to the others, may not seem like she has issues but just hides them away for the sake of her family and has stuff she's going through as well