Will mama hen take in a newly hatched chick along with hers?
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Definitely worth trying but I would put it under her tonight so that it has all night to bond. If you put it in the brooder and none of the other eggs hatch, it will be a lone chick which is never a good thing or you will need to steal a chick or two from her to put in the brooder with it and they won't take kindly to that.
I would be surprised if she doesn't accept it and you should know pretty quickly one way or the other. Make sure you put it under her with the back of your hand protecting it in case she pecks at you and hits the chick. Broodies can be a bit feisty sometimes.