If she goes broody, you can leave her in there until the eggs hatch. Many move them at that point, in case the others don't take well to the chicks (chicks have been killed by aggressive adults). You'll want to make sure that food and water are within close reach, as they don't tend to take care of themselves when they are broody. I took my broody off the nest every day (usually 2x a day) to encourage her to poop, eat and drink. She still weighs next to nothing now...lost a LOT of weight. I'd take treats to her daily as well to get some nutrients in her.