The faithful continue to gather at St. Peter's Square and churches around Rome to pray for the health of the pontiff.

Gandhi’s Scant Garb Bars Audience with Pope.” So read the headline of a New York Times report, from December 13, 1931, that the Vatican had cancelled a meeting between Pius XI and “the Indian nationalist leader” because the Pope thought he might be criticized “if he received the visitor in his usual scanty clothing.

Concerns over Pope Francis' health have mounted in recent years as have questions about his succession. Here's what we know.