5 weeks, no eggs, still sitting

[2overeasy]

I have researched the forums and can find nothing on this so I thought I'd ask.
I have two hens who are broody.
One hen started sitting several weeks ago - at least 4. I didn't mark the date as I usually do. I do know that we gave her 7 eggs at the time we moved her to one of the "nurseries" we have set up for broodies. Slowly but surely the eggs have basically disappeared. A few shells here and there. As of 3 days ago, the last egg was gone. Today she came off the nest and has not gone back.
The other hen has been sitting on golf balls for several weeks while I wait for a nursery to open up.
I've had hens in the past sit 21-ish days with no chicks, then get new eggs and sit 21-ish more and they had chicks. So these two are a bit different.

So, my question is: will a hen sit and sit and sit until she has chicks? Or do they just get over it at some point?

 

[polarbearpilot]

I don't know the answer to your question, but at a feed store near me, they do sell fertile eggs that are already 2 weeks or so into their development. So if you can find those, then your hens only have to sit for a week before they hatch. You do have to bring an incubator that can keep the eggs warm on the drive home from the store.

Just curious, what happened to the eggs? The hens ate them?