So me and my oldest sister came up with this Encanto au.
Julieta finds a random baby in the woods with weirdly shiny eyes a few weeks after Camilo is born and decides to take her in.
And that's how Mirabel joins the family.
But Mirabel is actually an abandoned changeling baby. Only Dolores and Bruno know this because of the very quiet tingling sound always around Mirabel and future vision.
Because of the miracle, Mirabels magic can't affect them. Except for the giftless ones(Agustin, Felix and Abuela) but its not that much. This version of fae, once they hear your name directly from you they have a lot of influence over you and you can't see their fae features(shiny eyes, pointy ears, etc).
At this point Camilos a girl with the name Mirabel and Mirabel has the name Camila.
So the day before 'Mirabel'(Camilo)s gift ceremony 'Camila'(Mirabel) asks "Hey you wanna swap names?" "Yes"
And so everyone but Dolores, Bruno, Camilo and Mirabels memory is changed to think Mirabel was always named that and Camilo was always named Camila.
And then when Camilo gets his gift the miracle predicts he's transmasc and so his door says Camilo instead of Camila and he gets shapeshifting. And now he's a boy.
About a year later they start putting together a scrap book they were procrastinating on making and get super confused when Mirabels labeled 'Camila' and Camilos labeled Mirabel. Camilo then walks by and finally tells everyone "oh yeah me and Mirabel swapped names! Neat huh?". And that's how the rest of the family realizes Mirabels a fae creature.
Half a decade later Antonios born and a few weeks after that a fae comes and tries to swap him with a changeling baby but Mirabels hissing like "No taking my cousin!" and the fae goes "Well we already got this kid, you want it?" and Mirabel goes "Yes! Free baby!"
Next morning Pepa and Felix come in and see two identical babies, one of which has sparkly eyes.
"Mirabel why is there two Antonios?" "Free baby"
And now Antonio has a twin named Fredrick.
The town is incredibly confused. First Mirabel is adopted, then she and Camilo apparently swap names(and whenever they try to call them by their original names, they physically can't, it just doesn't come out of their mouths) then Mirabel doesn't get a gift and none of her family is surprised by it(including Alma who just shrugs and says "shes already magical" whenever someone asks) and then half a decade later Antonio suddenly has a twin and the family just acts like he's always been there!
Theres a theory in town that Mirabels gift is that weird thing where her appearance changes to you when she hears your name and she just got it early to show shes officially part of the family since shes adopted.
Mirabel and Fredrick are specifically log changelings and because of Isabelas gift, she has some control over them. And by that I mean they believe whatever she says without question. "Hey the sky's green" "It is? When'd it change color?" For example. This only wears off once they learn about this weird effect.
Changelings feed on attention. It also substitutes food, a lot of attention from one person is equal to a pack of crackers. Good attention tastes sweet, and bad attention tastes sour. Julieta puts attention into her food and because of this Mirabel and Fredrick can tell how she was feeling when they eat it. Like the middle of breakfast.
Fredrick: *Trying to whisper* "Antonio, the food tastes bad"
Antonio: *Also trying to whisper* "Oh no, tia must be upset"
Fredrick: "Lets cheer her up!"
Antonio: "Yeah! Lets cheer her up with birds"
Fredrick: "I don't think that'll work"
Mirabel: *Laughing next to them because she knows Julieta was just frustrated about Isa ruining the garden or some other thing*
(This has been in my drafts for like 2 days btw)