Giotto (a.k.a. Giotto di Bondone)
tempera on panel
National Gallery of Art, Washington, D.C.
Is it just me, or does Jesus have an unusually well-styled head of hair in this painting? He doesn't really look like an infant. Of course, Giotto was one of the earliest artists to move away from the heavily stylized Byzantine style toward a more naturalistic style, so perhaps I should cut him some slack.
Detail images of this painting can be found at the National Gallery web site.