From MSNBC:
For Christians, ’tis the season for shepherds and kings, animals and angels to gather together around the manger — at least in countless Nativity scenes around the world. But it takes more than any one of the four Gospels to assemble that precise tableau: The three kings (actually, astrologers) come from Matthew, while the shepherds come from Luke.
Did we say four Gospels? Actually, in the early centuries of the Christian church, there were quite a few more than Matthew, Mark, Luke and John. For example, references to the ox and the donkey surrounding the infant Jesus come not from the four accepted gospels, but from an also-ran scripture called the Gospel of Pseudo-Matthew. Still other apocryphal texts portray the child Jesus as a divine “Dennis the Menace” — smarting off to his neighbors, giving his playmates a swift kick, even striking an offending youngster dead and then grudgingly bringing him back to life.
More here.