eastern phoebes - ornithology question

[Carole AM]

We have phoebes in our garage this year! Its been fun watching them.

 

[jwright215]

I just had my phoebes come back again this year to the same nest. I think they have been feeding a cow-bird baby. Last night I found three phoebe eggs broken on the ground, as if they were thrown from the nest. This morning I went to check on the mama and found her dead on the ground.... Does anyone know what could have happened to my poor phoebe....