Which singer did Mariah Carey sing backup for before her solo breakthrough?

Before her solo breakthrough, Mariah Carey sang backup for Brenda K. Starr. Carey worked as one of Starr's backing vocalists in the late 1980s, a period when she was still trying to establish herself as a songwriter and singer.

The connection became a major turning point in Carey's career. Starr reportedly helped Carey get her demo tape into the hands of Columbia Records executive Tommy Mottola. After hearing Carey sing, Mottola signed her to Columbia, where she began preparing her self-titled debut album. That album produced the 1990 hit "Vision of Love" and launched Carey as a major recording artist.

Carey later paid tribute to Starr by recording "I Still Believe," originally Starr's 1988 hit, for her 1998 compilation #1's. Carey said Starr had treated her like a younger sister and supported her when she had little money or industry recognition. This early professional relationship is why Starr is the clear answer, rather than another famous vocalist such as Whitney Houston, Celine Dion, or Gloria Estefan. Those singers were contemporaries and influences, but they were not the artist Carey backed before becoming a solo star.