we have 3 of 5 eggs that started to hatch last night at 6pm. One chick is out and drying in the incubator the other 2 eggs have a nice size hole of shell off, but just a hole. They are still alive...I can still hear them chirping. They don't seem to be making any progress since about 9pm. I have had a little difficulty getting the humidity as high as suggested, but wondering...do I let them alone? How long do I wait before I try to chip away some of the shell?