Pope Francis will answer children's questions in a new book to be published in March. The Vatican Christmas tree will be unveiled early on December 8, the start of the Year of Mercy. Air space over Rome will be closed during Year of Mercy events to prevent drone attacks, Italian authorities have said. Paul Moses says the Vatican is pursuing a "disastrous course" by investigating journalists over alleged leaks. John Allen considers who will succeed Pope Francis. Fr Anthony Ruff explains what was at stake when the US bishops' debated the Book of the Chair yesterday. And Susanna and Mark Spencer review the Vatican list of the world's greatest films 20 years after it was first published. Follow me on Twitter @lukecoppen for updates throughout the day.