[1] Avellanet was born in San Juan, Puerto Rico, where he became a teen idol across Latin America after being hired by Edgardo Diaz as a member of Menudo in 1988, alongside Ricky Martin.

The album Sentir (1999), produced by Isidro Infante, had success in several Latin American countries, and in New York and Puerto Rico.

The album was promoted by its lead single, "Miente", a cover of Enrique Iglesias's song which became a top-ten hit on the Billboard Tropical Airplay chart.

In 2003 Avellanet and his former Menudo bandmates (Sergio, Ruben, Angelo and Rawy) made a reunion tour, naming it Los Ultimos Heroes.

In 2011 Robert moved to Los Angeles, California to pursue a career in acting and throughout the next decade he worked in several TV series, films and commercials, and also released several music singles.

Also in 2022 Robert founded Viva La Earth, a skin cream company that supports non-profit organizations, such as The Wayuu Taya Foundation.

[10] It was directed by Angel Manuel Soto, and premiered at the Tribeca Film Festival, then released for streaming on HBO Max on June 23, 2022.