I've put day 12 incubator eggs under a newly broody hen and she hatched them fine, so I think your hen and eggs would be fine.Quick question....I have another hen that has decided to go broody which I am Ok with. She has been setting for about 3 days, the eggs are infertile, but I have a few bantam cochins eggs in the incubator that are on day 13. Can I give those eggs to her or does she need to set for a certain number of days? I'd rather her just hatch and raise them.