Pope Francis celebrates 81st birthday

Children hold balloons shaped in the number 81 on the occasion of Pope Francis' 81 birthday during a private audience with children assisted by "Dispensario Santa Marta", a Vatican pediatric clinic, in the Paul VI hall at the Vatican, Sunday, Dec. 17, 2017. L'OSSERVATORE ROMANO via AP

This handout picture released by Roman pastry Hedera Sweetness and Co. shows a birthday cake offered to Pope Francis for his 81st birthday, on Dec. 17, 2017 in Rome. The cake is decorated with a drawing by Italian street artist Mauro Pallotta a.k.a. Maupal. AFP/Getty Images

Pope Francis hugs a child on the occasion of his 81st birthday during a private audience with children at the Vatican, Sunday, Dec. 17, 2017. L'OSSERVATORE ROMANO via AP

Faithful hold placards reading "Best Wishes" on the occasion of Pope Francis' 81 birthday prior to the start of the Angelus noon prayer in St. Peter's Square at the Vatican, Sunday, Dec. 17, 2017. Gregorio Borgia, AP

Pope Francis gestures during the Angelus noon prayer in St. Peter's Square at the Vatican, Sunday, Dec. 17, 2017. The pontiff is celebrating his 81st birthday. Gregorio Borgia, AP

Pope Francis blows out a candle on the occasion of his 81st birthday during a private audience with children in the Paul VI hall at the Vatican, Sunday, Dec. 17, 2017. L'OSSERVATORE ROMANO via AP