About a week ago a single duckling hatched under a hen. She ignored it and after 2 days I brought it inside. A week later two more hatched and they moved inside the brooder box.
They were doing great inside learning how to used the water bottle and eat.
But then I went into the coop and found 3 dead ducklings killed by a hen.
I saved the rest and they are now inside the brooder with the older ones.