When the eggs were a day overdue, I candled them again, and I could tell that they were not viable. Since I'm curious, I sealed them in a ziploc bag, and opened them all up.
1 egg stopped developing around day 13-14.
3 eggs stopped developing around day 10.
1 egg stopped developing around day 7
1 egg stopped around day 3-4.
I'll admit that I'm pretty upset about it. I had an emotional attachment to the idea of hatching MY chickens' eggs. It would've been nice to have a legacy. I didn't cry when I found my chickens dead and had to bury them, though I wanted to. I did cry a little when I realized the eggs weren't going to hatch. I think that it was also for the loss of the hens as well- I'd pinned my hopes on these eggs. Also, to see that they had started developing and died for some reason was difficult. I wondered what I'd done wrong, and if it could have been prevented.
I mailed my incubator back to Brinsea today. The autoturn feature on it was broken, and they'd given me a return authorization so I could get it repaired. When the chicken tragedy struck, I wanted to try to hatch before I sent it back. Hopefully I'll get it back in a month or so.
Once it comes back, I will do a test incubation at home to make sure it's turning the eggs ok and will hatch successfully. Then, I'll do a couple incubations at my kids' schools. I mentioned it in casual conversation, and I have three teachers at three schools who are really excited at the idea of hatching chicks in class.
I'm embarrassed to admit I'm so broken up over some birds.