The hen will continue to sit on the baby and the eggs until they are all hatched, and the chicks have started to feather up. The babies will need her body warmth to stay alive, so don't worry about her being in the nest, that's where she is supposed to be.
If she's freaking out whenever you go near, then it's best to keep your distance for now. She needs to concentrate on feeding her chick and keeping eggs warm. You don't want to disturb her so much that she abandons the nest.
The dad will eventually start taking care of mom and the chicks, and will be more involved when the chicks start getting bigger.
I assume this is your first time allowing your birds to breed?