When we've had eggs under a hen and know they are going to hatch a day or two apart, we do take the chicks as they hatch and then put them under the hen after dark when they've all hatched. It has worked well so far. We also pull them as they hatch because I don't want the other chickens to eat the chicks if they fall out of the nest box waiting for the other ones to hatch. We then put Mom and babies in a seperate pen. Of course, every hen is different and it's certainly best if all eggs are due to hatch at the same time. Good luck!