First time broody, sitting on four eggs. All still alive as they all rocked in water test. A friend who has kept and bred chickens for years made a hole in the air sac end of the egg to see if the chick was stuck. There are still blood vessels visible, membrane intact so she said leave it under hen. I am concerned that this broody is taking so long. No peeps or anything. But chicks are still alive. Could it be that they are taking longer to develop due to her being first broody.