It has been a week since four of the five eggs hatched. The fifth remained unhatched. The chicks have grown from tiny floppy pink things hardly able to hold up their heads to be several times larger with a first covering of feathers.
They now make a soft cheeping sound but I don't think they can yet open their eyes. The parents are feeding them very regularly, mostly with caterpillars.
You can see the unhatched egg in this video, which gives a good idea of how much they have grown.
Sometimes the father doesn't seem to be able to decide which chick deserves the food.