The swallows and sparrows are very pleased to find a place on the roof of the hall for their nests.
The mother birds are feeding their babies with pleasure, which assumes a scene of peace and harmony.
But they have never thought of the following scene: the chimney at the top of the kitchen might break, the fire might leap up to the roof and the burning purling might destroy their nests.
But those swallows and sparrows are unmindful of the coming disaster.
They go on with their superficial happiness brought by peace and calm.