The girls' parents were gospel singers, and before long the children were singing in their local church choir, eventually turning up on the Bobby Jones Gospel show on BET. The siblings joined the Michael Matthews traveling gospel show Mama I'm Sorry in 1995, followed by a second Matthews production, Sneaky. Each sister subsequently toured as a backup singer for a variety of R&B acts.

Meanwhile, they wrote contemporary gospel material with crossover appeal. A meeting with producer Warryn Campbell (who would eventually marry Erica) led to a song publishing deal, and "Dance," a song the sisters wrote and performed with Robin S., appeared on the soundtrack to Dr. Doolittle in 1998. Later that year, "Let Go, Let God" was used on The Prince of Egypt -- Inspirational, and their songs were also recorded by 702 and Yolanda Adams. Mary Mary then signed as a recording act to Columbia/C2 Records and released the debut single "Shackles (Praise You)," a Top Ten R&B and Top 40 Hot 100 hit that was followed by the album Thankful in May 2000. Thankful was a huge success with Christian audiences, offering a younger, hipper version of gospel that audiences could relate to.

Two years later, the duo released Incredible, an album whose material was largely written by the sisters themselves. Both Erica and Tina became mothers before their self-titled album appeared in 2005. It was the duo's first album to enter the Top Ten of the Billboard 200 chart. The Sound, released in 2008, performed even better; it debuted at number seven and was Mary Mary's most crossover-savvy album yet, benefiting from Campbell's role as the set's sole producer. Two singles, "Get Up" and "God in Me," topped the Dance Music/Club Play chart, while the latter also hit number one on the Hot Gospel Songs chart. Something Big, featuring productions from Campbell and a handful of fellow collaborators, was issued in 2011. The next year, they starred in a We channel reality series, Go Get It, and released a soundtrack -- featuring old and new material -- that May. ~ William Ruhlmann