How long do I wait?

[Lacrystol]

I have 11 silkie eggs in Lockdown, today is the 21st day, I heard one of them peeping yesterday about 10:30. There are no cracks yet, how long should I wait for before I should step in and help? How long can a chick after peeping, live in a shell? I don't want to lose them...

 

[Lroach711]

Everything I've read says to wait up to 25 days. Different variables apparently can cause a delayed hatch. I've also read to just let nature take it's course and not to help the chicks unless absolutely necessary because they usually end up dying if you help them. I am new to this though..so maybe someone with more experience will reply.