I have a barred rock that is broody, 21 days today, she was sitting on 9 eggs and seems only one was fertile (you can see the shadow-it looks like a dark blob and looks like veins in the egg but I cant tell if the chick is still alive)...I had a lady give me a couple duck eggs and I have a couple bantam eggs Im pretty sure are fertile. I have placed them under her...so I need her to sit another 21 days, will she do this even if the one hatches? How can I tell if the chick is still alive in the egg? If it does hatch & I take it from her will she continue to sit? Thanks so much for all your help.