VATICAN CITY — A somber Pope Francis steeped his Christmas message to the world Thursday in sadness for those with little cause for joy — abused children, refugees, hostages and others suffering from violence in the Middle East, Africa, Ukraine and elsewhere. Anguish for children who suffer maltreatment or violence, including in the recent terrorist attack on a Pakistani military school, tempered the pontiff's traditional Christmas Day speech, which he delivered from the central balcony of St. Peter's Basilica. A crowd, estimated by the Vatican to number more than 80,000 Romans, tourists and pilgrims, filled St. Peter's Square for the "Urbi et Orbi" message (Latin for "to the city and to the world").