Pope Francis, who has been hospitalised for two weeks battling double pneumonia, has spent another peaceful night and is now resting, the Vatican said on Friday. Francis, 88, was admitted to Rome's Gemelli hospital on February 14 with what was originally described as a bronchitis and was later revealed to have developed into something more serious.

Pope Francis is continuing to improve, according to the Vatican, which said he spent Thursday alternating between high-flow oxygen therapy and a Ventimask.

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