There are three cases in the world, and Leo is the only one in South America (He is a child who was born speaking English)
https://youtu.be/OQgJAtSE4Vs?si=sJ5-mBEoMZXE_qeE
His parents believed he was deaf and mute because he couldn't communicate with them when they spoke to him in Spanish.
The first time he spoke, at age 4, it was in English.
No one knows how he learned it, nor does he himself.