The massacre of infant boys by King Herod as told in Matthew 2: 13 - 18 doesn't often feature on Christmas cards - that would be too grisly. Such cruel images would spoil sentimental Christmas pictures. But a nostalgic and sanitised Christmas card scene was not the world into which Jesus was born and it is not the world in which we live.
In a world where so many vulnerable children do suffer neglect, hunger, abuse and even murder, where tyrants still crush the powerless, the story of the murdered babies of Bethlehem still speaks into today's real world. The grief of parents who suffer the death of their children, for whatever reason, is still a universal story. The suffering of those forced by oppressive regimes to flee as refugees still goes on.
Image: photo of wood-sculpture in the grounds of Our Lady of Guadalope Abbey, New Mexico, depicting "Rachel weeping for her children". Source of photo is here.