I had 13 eggs under a broody. Today is day 28. Yesterday there were two chicks, both dead it appears right out of the egg. I got a couple of 5 day old chicks to put under her, but when I tried it last night she pecked at them so I took them and six of the remaining eggs out. I put the eggs into the incubator. This morning two are opened. One had a chick in it, but it's dead. It doesn't appear that the chick hatched itself, it looks like the side blew out of the egg. The other egg looks the same except it is filled with a grey liquid and no chick. What's up? Is it just that they are too old to hatch?