Quezada and her family—her mother, Australia, and siblings, Rafael, Jocelyn, and Martín, moved to Washington Heights, Manhattan in order to escape the Dominican Civil War.

[2] Quezada spent her pre-teen and teen years in Washington Heights, which was a central point in the Latin music boom of the era.

Her musical inclinations developed as a pastime in the streets of Washington Heights where she formed with her brothers and sister, the group that would become known as Milly, Jocelyn & Los Vecinos.

In more recent years, Quezada has released music that collaborated with various artists such as Fefita la Grande, Maridalia Hernández, Gilberto Santa Rosa, Pavel Núñez, Héctor Acosta, Ilegales, Antony Santos, and Olga Tañón.

She performed at venues such as the Coca-Cola Music Hall in San Juan, Puerto Rico and Eduardo Brito National Theater in her native Santo Domingo.

Her well known Carnaval Song "La Guacherna" written by Esther Forero, is recognized along with Barranquilla's Carnival by the coveted "Worldwide Cultural Heritage" issued by UNESCO.

The movie features an original song, La Puerta del Nuevo Mundo that is a once-in-a-lifetime collaboration of the twelve stars.

In 2022, a biopic about Quezada, titled MILLY Queen of Merengue, was announced starring Sandy Hernandez and directed by Leticia Tonos.

Quezada has recorded many solo albums, receiving a Latin Grammy Award for Pienso asi, MQ and Aquí Estoy Yo.