I have a guinea that pipped the shell last night sometime but I didn't see a beak (no hole visible in membrane), and I realized a couple of hours later that the shell is cracked all the way around but I can't see any openings in the membrane. I just don't get how it's possible that the egg can crack without the membrane breaking. Three have hatched fine so far and another needed help - after nearly 3 days! The one I helped had a very tough shell with big pieces that broke away, not tiny...and the membrane was definitely thicker than a chicken egg. I don't see the "breathing" movement, but I'm so new to this I don't know whether that's always after they are actually breathing air. I can't see through the membrane at all to see where the beak is anyway, even if I eventually wanted to help. Should I be prepared to help tomorrow if it doesn't pop out later? Is this guinea normal? I'm not worried that this one is late (it's day 28). The eggs were split between two different incubators at slightly different temps/humidity until lockdown. This is one of 4 remaining - no other pips.