killed by hen

I have a black copper marans who recently went broody for the first time so I gave her 6 eggs. She successfully hatched 5 of them and then the next day she killed them all. When I found them she was still sitting on the nest because there were still two eggs under her that were laid by other...

She hatched 4 already then this egg hatched this am and she has 4 more to go... well 4/5 hours later I find her and the other chicks EATING it alive while it screamed. They ate out the eyes, ears, and hollowed out her abdomen from the vent... I ended up having to kill it cause it was still...