By Cherri Gregg

PHILADELPHIA (CBS) — A choir of Philadelphia professionals will back up the headliners for tonight’s Festival of Families.

The Philadelphia Heritage Chorale is made up of 60 trained voices.

“The rainbow comes together to sing music of classical literature to the music of the African Diaspora,” says Dr. J. Donald Dumpson, founder and artistic director.

He says the chorale will perform half a dozen selections in 3 languages and providing the chorus for Aretha Franklin, Andrea Bocelli and Juanes. Amazing Grace and the Lord’s Prayer are among the songs they’ll sing.

“To sing in the soulful gospel style of Aretha Franklin and then to follow it with Porcini- is a tall order,” he says, “but they are hitting the benchmarks we set.”

The singers rang from high school students to the head to the Temple voice department. Most in the choir possess musical training and despite limited group rehearsal, they worked alone and are up to the task.

“I’m so excited, but we’re humbled for this…absolutely,” says Christine Anderson and Valerie Gay, “to be singing for the pope.”

They will wear black choir robes and pearls along with comfortable shoes tonight as they stand on a small strange with the Philadelphia orchestra for this historic performance.

“For us to be in the music, that is something that’s so special,” says Gay.

“It is truly the universal language,” says Anderson.

The Festival of Families begins tonight at 6:30 p.m.