I am so, so saddened and confused. A bantam broody hatched out 1 chick on her own (the eggs had originally started under another broody who abandoned the eggs, hence the low hatch rate), and I grafted 6 others from the feed store onto her. She'd been broody for over a month so it wasn't like she wasn't ready for the eggs to hatch. And she accepted the new chicks happily, and for days (almost a week) seemed totally smitten with her brood... leading them to food and water, snuggling down with them at night, etc. Then, this morning, we found 4 of the 7 dead. Clearly killed -- on a couple of them the organs were protruding and they had peck marks on them. It seems she targeted certain color chicks, too: she killed all three of the barred rocks and the darkest of the Ameraucanas. (The original chick she'd hatched out was a splash orpington.) Has anyone had this happen before? I understand that some mothers won't accept grafted chicks, or that chickens won't accept chicks if they haven't been broody for at least 21 days. But that didn't seem to be the case here. She accepted these chicks, and then suddenly killed them. I am so confused, and feel terrible for those poor little babies. Needless to say her parenting privileges have been revoked, the surviving chicks have been put in a brooder and she's back in the coop with the other chickens.