Putting baby chicks in the coop.
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Definitely separate them! They are still too small to stand up to the big chickens. Keep them separated for about another month, until they are a good size. Then if you have a big yard let them out with the others and watch them. The bigger the yard the better it will be for them.
And if you can section off a little area for the chicks outside. It will help them get used to it before you put them with the others.