Not all broodies know what they're doing. Keep an eye on her and don't trust her 100%. I know a lot of people like to emphasize that a broody (or nature) knows best, but chickens are very far removed from nature at this point - especially the pure breeds, that have had selection pressure on them for other things, and have lost the reliability of instinct. A lot of breeds are propagated artificially - via incubators, or broodies of different breeds - and would go extinct if left to "nature".
I'm dealing with a very disappointing broody right now that's missing a lot of the instincts, though she's trying, poor thing. She's learning, but she needs a lot of help. Make sure she's tucking the eggs under herself, isn't pecking the chicks really hard after they hatch, keeps them under herself after they hatch, takes them out of the nest after a couple of days, shows them food and water, etc. Watch what she does in tricky situations and what decisions she makes, and show her the way if she makes a wrong decision. For example, mine wasn't taking the chicks out of the nest. 3 days after hatch, they started hopping out on their own. One chick stayed in the nest and she stayed with that one chick, leaving the rest unattended on the floor, cold and lost and calling for her. The nest is low and they have a ramp, so they could theoretically get back up if she showed them, but she didn't. I don't know how long they were like that, stranded and cold - I had to go and pull her out of the nest, and put the last chick on the floor so they could all be together. Staying in the nest with that one chick was a bad decision. What she should have done was come out and call the last chick, which would've followed her down the ramp and to the floor, so the whole family could be together. Also, usually once they leave the nest, they don't return - the hen settles on the floor with the chicks at night. My hen went back into the nest in the evening though, and just sat there. The chicks were left at the bottom of the ramp, cheeping in distress. She wasn't calling them over or anything, or showing them how to use the ramp. She just sat in the nest and waited. I had to lift them up and put them under her. I'm just going to block the nest for tonight.
By comparison, I have a better broody that used the same nest and the same ramp last year, but she never left the brood split like that. For the ramp, she'd stand halfway down and call the chicks, then move some and call them again, and show them gradually. Then once they were down, she didn't return to the nest, they slept on the floor from then on, and she always had all of them together. For both hens, it was their first time. Some just know better than others. Hope yours has all her instincts, but keep an eye on her just in case!
