Sasha Sierra Allen is an American singer and actress. Born and raised in Harlem, New York, she began her career in the music industry as a backing vocalist for Christina Aguilera, Alicia Keys, John Legend, Leona Lewis, and Usher. In January 2016, she joined the Rolling Stones touring band. In May 2020, she joined The Pussycat Dolls touring band.

The fourth season of the American reality talent show The Voice premiered on March 25, 2013, on NBC and was hosted by Carson Daly, while Christina Milian returned as the social media correspondent. Coaches Adam Levine, and Blake Shelton returned as coaches, both for their fourth season. CeeLo Green and Christina Aguilera appeared as performers instead of coaches. Two new coaches Shakira and Usher served as replacement coaches for Aguilera and Green, leaving Levine & Shelton the only coaches remaining from the inaugural season. The team sizes were trimmed back down to 12 per team, with each coach having two 'steals' in the Battle Rounds.