You can relax, MOST hens are fantastic mamas, and it's one of the most enjoyable aspects of chicken keeping to watch one carefully tending her brood. Sure, there is the rare exception, a hen who will hurt or kill her chicks, but you may go your whole life and never own a hen like that. I haven't yet.
A tractor will be a nice place to keep both Mama & chicks. Then when you begin to notice evidence that the hen is done with the chicks, you can put her back with her former flock-mates & keep the chicks together in the tractor until they're grown.
Another thing to start planning is what you'll do with the roos you get from this clutch, and what method you'd use if -- God forbid! -- you have to cull an ailing chick.