Another chick fell out of the nest and died today. I saw the original owner of the nest, the Swallow, do battle several times with the Sparrow trying to "evict" her. I think the Sparrow feels she has squatting rights! My cat was again guarding the little chick from the other cats and hissing if they came close. She was not hurting it at all, just mothering it. I buried it with it's sibling in the garden. The last little chick probably has only 1 week left before it can fly. I hope it makes it!