Faithful gathered at St. Peter's Square in the Vatican and outside Rome's Gemelli Hospital on Monday (February 24) as Pope Francis remains critically ill but alert, according to the Vatican. Could these jumping mice change how astronauts exercise?

Catholics Pray for Pope Francis as He Battles Pneumonia On Tuesday night, the Vatican said the pope was in “critical but stable” condition. Advertisement NOW PLAYING 1:14 2:46 Advertisement 0:33 0:54

While the Vatican has detailed laws and rituals to ensure the transfer of power when a pope dies or resigns, they do not apply if he is sick or even unconscious.

Faithful around the world worry and pray for the Pope's condition during the longest hospital stay of his papacy.

Catholics in Buenos Aires attended Mass on Sunday to pray for Pope Francis' recovery. (Video by Cristian Kovadloff)

Prayers are pouring in from parishioners all across San Diego after Pope Francis was listed in critical condition.

The pope looms so large in everyday Italian life that there are lots of expressions that make light of even a dark event like his death.

For centuries, one of the biggest taboos at the Vatican was openly discussing the pope's health. As leader of the world's 1.4 billion Catholics, the pope is a revered spiritual figure. Talking about his earthly health was profane.

A man revered by millions as the “doctor of the poor” will be the first saint from Venezuela. Pope Francis approved a decree Tuesday but did not set a date for the canonization of Dr.