Sister2Sister or S2S are an Australian duo comprising the Muscat sisters, Christine and Sharon, who were pop singers, songwriters and television presenters. Their debut album, One (June 2000), peaked at No. 3 on the ARIA Albums Chart. It provided two top five singles, "Sister" (1999) and "What's a Girl to Do?" (2000). At the ARIA Music Awards of 2000 "Sister" won Best Independent Release. From 2001 they undertook a career as television presenters, as VJs on MTV Hits, and subsequently opened the Sister2Sister School of Singing in 2004.