June 27: Tragedy

Just got home from work, and found a tiny dead chick on the drive.It must be from the house martins' nest above the porch. I buried it in the border, then looked carefully at the nest. There is enough mess on the porch roof to indicate that the eggs have hatched, but there are 2 more tiny bodies on the porch roof! I'll have to get the steps out later and remove them.
What's gone wrong? It's been chilly the last few days, and it's rained, but for 3 chicks to die is awful.