Broody crushed baby! HELP

[Mel Lloyd]

This is Broody's first time, and we had 4 eggs under her (large Cochin), the first just hatched assumingly in the middle of the night, and she smashed it to death.
We also have 2 additional eggs in an incubator, and both are fertile, but only at 5 days, the eggs under her are at 18 and 17.
Should we take the remaining 3 away from Broody and put in incubator to keep an eye on them?
When/if they hatch, do we keep them separate from Broody or put her in a secluded pen/coop with the babies?
First time parent, any suggestions are appreciated!

 

[azygous]

Having a staggered hatch can confuse a broody, but I'm not saying that the flattened chick was due to this. Sometimes a chick dies closely following hatch and it only appears the broody squashed it. I found such a tiny corpse under my broody once. She has always been a very attentive broody mom, and her other chicks were fine.

If you are having misgivings about your broody, then you need to gather up the remaining eggs and incubate them and brood them yourself.