Which new member and lead singer did the American band The Black Eyed Peas acquire in 2003?

Explanation

The Black Eyed Peas is an American hip-hop and R&B band formed in 1995. Its members are Will Adams, Jaime Gomez, Stacy Ferguson and Allen Pineda, who were all born within a single year - November 1974 to July 1975. Kim Hill was the original lead singer. The band has released the albums "Behind The Front" (1998), "Bringing The Gap" (2000), "Elephunk" (2003), "Monkey Business" (2005), "The E.N.D." (2009) and "The Beginning" (2010).