I bought an incubator because someone told me hens will not brood until they are a year old. For this same reason, I had no nest boxes or anything set up yet. Anyway, a week after I bought my incubator, one of the hens starting sitting on some eggs. I peeked and she had 11 of them. I just let her be, but I noticed I wasn't seeing very many eggs around so today I looked into the coop and two hens were sitting together on the eggs. I moved them to see, and they had 31 eggs (yes 31). Tonight I went out and candled them and of the 31, 20 are developing, but they look like some are in different stages of development. I left the 20 there, but will they be OK with hatching at different times, and two hens sitting on them? Is there anything I should do?