It's a poem whose author, W.H. Auden, employs ekphrasis = verbal description of paintings (more broadly, this term signifies description of objects of visual art and even more broadly, any translation of the visual into the verbal)
the theme of the poem is that when any human being suffers world goes on their daily routine. people dont care about anyone if they are happy then they do not care anyone is sad and they even do not...
It is not. Some people say that not carrying for others suffering is a reference to the holocaust. But the poem was written before agressions against jews.
The miraculous birth refers to jesus and how the old are waiting very curious while the children tht dont understand this stuff prefer to have fun or that they are just ignorant of what importance is...