The daughter of Elijah Joshua Reeves and Ruby Lee Gilmore, Lois was part of a family of 11 children. Before her older sister, Martha, was a year old, the family moved from Eufaula, Alabama to Detroit. Both Elijah and Ruby enjoyed singing and playing the guitar, passing their love of music on to their children. Elijah's father, Reverend Elijah Reeves, was a minister at Detroit's Metropolitan Church; the family was very active in the church and in its choir.
Upon graduatation from high school, Lois Reeves began to travel extensively with her older sister, Martha Reeves, and her musical group, the Vandellas. As she watched the shows from the wings almost nightly, she knew the music and routines perfectly. It all happened by surprise for the teenaged Lois. One night she was in the wings; the next night, barely 18 years of age, she was asked by her sister to replace Betty Kelly. The group put Lois' business knowledge to work; she took care of the bookkeeping, hotel reservations, travel arrangements and also helped negotiate contracts.
Though never under contract to Motown Records, she was under contract to Martha Reeves, and later found herself singing on the Vandellas' singles "Love Bug Leave My Heart Alone" and "Honey Chile", the latter of which was when the group was known as Martha Reeves and the Vandellas. Lois was the youngest member of the Vandellas throughout its tenure and performed with the group in Japan, UK and Spain. She also performed with the group when they successfully opened at the renowned Copacabana nightclub in New York. Lois appeared with the group on The Mike Douglas Show in 1968 and Soul Train in 1971.
Lois and original Vandellas member Rosalind Ashford often had to share background work with The Andantes behind Martha as Motown was limiting the sounds of background vocals. Since the Andantes played a pivotal role in the Motown sound, it's often confusing as to which actual member of the Vandellas sung on the recordings with Martha. It's confirmed, though, that Lois sung on Vandellas hits such as "I Should Be Proud" and "Bless You" and the entire Black Magic album, the Vandellas' final album, released in 1972.
Lois Reeves heavily contributed to the group's choreography. especially when Sandy Tilly joined the group in 1969. The two are considered by Martha as the best dancers and most elegant of the all the Vandella line-ups.