Miguel sings the song in a bid to capture the attention of Ernesto de la Cruz. He was eventually singing the song while running after Ernesto, though the song was interrupted when Miguel fell into the pool.
Señoras y señores Buenas tardes, buenas noches Buenas noches, buenas tardes Señoritas y señores
To be here with you tonight
Brings me joy, que alegría
For this music is my language and the world es mi familia
For this music is my language and the world es mi familia(x2)
For this music is my language --
Although the song features Ernesto singing with Miguel in the film's soundtrack, Ernesto does not actually sing with Miguel in the film; in the film, Ernesto is singing it in one of his films in the background.
As shown in a flashback, the song was seen in Héctor's songbook, confirming he was the one who wrote it.