In 1959, McGlown started dating future Temptations member Paul Williams, who was then singing with the Primes. Around the same time, the Primes' booking agent and manager Milton Jenkins was scouting the Detroit neighborhoods looking for girls to become part of the Primes' sister act. After he discovered Florence Ballard, Ballard set about recruiting other girls she knew, quickly asking Mary Wilson. Primes member Paul Williams asked Diana Ross to join. Due to her connection with Williams, McGlown became the last to join the Primettes.
Along with their guitarist, Marv Tarplin, the girls performed for Berry Gordy who, although impressed, told them they were too young for the business and encouraged them to finish school. On Lu Pine Records, McGlown sang backing vocals for Mary Wilson on "Pretty Baby" and backing vocals for Diana Ross on "Tears of Sorrow". These became the only known recordings of McGlown, although her voice does not stand out by itself in either song.
While all four members sang lead on stage, it is only the other three members who ever had leads on studio recordings. McGlown eventually became Mrs. Betty Travis and left the Primettes in 1960 to concentrate on her new marriage. She was replaced by Barbara Martin the same year.
Chronology(The band's name history: The Primettes 1959–1961 / The Supremes 1961–1967 / Diana Ross & The Supremes 1967–1970 / The Supremes 1970 / Diana Ross & The Supremes 1970 / The Supremes 1970–)