The single, which features all four members — Felipe Colombo, Benjamín Rojas, Camila Bordonaba and Luisana Lopilato — was written by recognized Argentine director, producer and composer Cris Morena.
"Sweet Baby" was written by Cris Morena and Carlos Nilson, who wrote most of the songs for Erreway albums Señales (2002), Tiempo (2003) and Memoria (2004).
"Sweet Baby" features all band members — Felipe Colombo, Benjamín Rojas, Camila Bordonaba and Luisana Lopilato — as leading vocals.
In the series, the song was written by Mía Colucci, the character of Luisana Lopilato.
At the time, the band consisted of Marizza Pía Spirito (Camila Bordonaba), Pablo Bustamante (Benjamín Rojas), Manuel Aguirre (Felipe Colombo) and Felicitas "Feli" Mitre (Ángeles Balbiani), but they performed it with Mía after Feli had left.