Feeding blackbird chicks

Hi all

I was cutting hedges the other day stumbled across a blackbird nest. 5 eggs and none hatched. Today one has hatched and I assume the other will shortly follow. I see the mother bird coming and going frequently, I assume for food. My problem is that it is a very very small garden and we are due to have a large number of people over for a family function this weekend. I dont want to cause the chick's any harm. Is it imperative they eat every so often as there is no chance thr mother will come to the nest whilst there are people in the garden and its likely to be that way for around 7 hours.