I had been planning to get into that spot to prunes the branches of our next-door neighbour's leylandii trees and to cut back the ivy (also from our neighbour's garden) which cascades over the fence and has grown a bit too thick. Obviously, I will now have to wait until the robin's have finished their business. The perfect excuse for doing nothing.
And here is one of the parents. Not the greatest example of wildlife photography but I'm not unhappy with it. (For our cousins across the pond, this is a European robin, erithacus rubecula, 5" in length, little more than half the size of the American robin.)