Within an hour of the start of a festival headlined by Pope Francis, Mark Wahlberg already had made a joke about his raunchy movie "Ted."

The actor was the master of ceremonies Saturday night while Francis sat on stage to hear from families and musical performances at the World Meeting of Families event.

After Bobby Hill, 14, of the Keystone State Boychoir performed an opera solo, he told Wahlberg that he liked his performance in the movie about an angry talking teddy bear.

"He whispered in my ear that he liked the movie 'Ted,'" Wahlberg said. "I told him that was not appropriate for his age. Holy Father, please forgive me."

The Boston-born actor, who also played Vince Papale in "Invincible," a film about a real-life walk-on who signed with the Philadelphia Eagles in the 1970s, also gave a "Go Eagles!" cheer from the stage.

He is introducing performances by Aretha Franklin, Andrea Bocelli, The Fray and others.

Bobby, a soprano from Philadelphia, sang "Pie Jesu" by Andrew Lloyd Webber. He presented Francis with a rock that the choir brought back from its trip to Antarctica.