Chicken newbie here- I have a small flock- 8 hens and a rooster. One hen got broody so I saved out eggs for 3 days til I got 12. Marked them with crayons and let her sit on them. They started hatching slowly. So far 7 healthy chicks over 4 days. She's still sitting on the other eggs and I can hear cheeping in one unhatched egg. Shouldn't they have hatched in a shorter time period? How long should I let her sit on the others before giving up? I thought they would have hatched all at once. Any info is appreciated. Is this normal? Thanks for comments.