pink02:

Ohh! For those who don’t know, Carlos was the supposed name of Camilo Madrigal in the making of the movie.

This would just be the whole explanation since many have already asked who Carlos really is-

The producers changed his name to Camilo right after they met the tour guide— Camilo, as they tour around Colombia to seek inspiration for the story. Hence Carlos was out of the game.

In the concept arts, early designs for Camilo was far more edgy and has the color coordinates from red to maroon.

Many fans saw this and was intrigued by the emo teen concept to which they brought back Carlos. Mainly was designed as the jerk cousin but as Jared Bush said, it was later passed down to Isabela to which is now being the mean sibling.

For Carlos, like in the early concepts, people portray him as the jerk, angry teen with an edgy personality. And many fans (coughs) fangirled (?) Over it and then made him into the non-cannon twin of Camilo since they both, well, have the same type of gift.

Some headcanon say his gift was to shapeshift into different animals and some, like me, would headcanon him having the same gift as Camilo to which shapeshift into people.

The bad boy teen was loved and confused many since he popped out of nowhere after the movie was out. But yeah, that’s the whole concept why Carlos exists.