Breaking News Alert: Punkin just hatched her first chick! While I was trying to catch up on this thread, as a matter of fact.
Turns out I originally counted the day she went broody, but I actually placed the eggs under her two days later, so today IS Day 21. (Figured that out last night as I worried about them being late...)
I was afraid she was going to kill the chick, as she pulled it out from under her and picked it up and dropped it - in the nest, though, and only about an inch - but then she tucked it beneath her tummy. Maybe she was pulling it out of the shell? It's cheeping there, now.
I will be stuck here on the sofa watching her. This is quite different from finding a broody hen with chicks, or using an incubator.