Pope Francis contemplates aging on his 80th birthday

VATICAN CITY -- Pope Francis celebrated an active if low-key 80th birthday on Saturday, sharing breakfast with eight homeless people before celebrating Mass with cardinals as greetings flowed in from around the world.Play VIDEOPope's choir spreads message of harmony in musicThe pope chatted individually with each of the homeless guests - four Italians, two Romanians, a Moldovan and a Peruvian - at the Vatican hotel where he resides, and shared Argentinian cakes with them before heading to Mass,