I have a broody Cochin that has been sitting on a clutch of 9 eggs for 14 days. Tonight I candled them for the second time and SURPRISE she is now sitting on 10 eggs! I candled the new egg and it is of course fertile but looks to be about a week behind the others in development. I plan to leave it until the others hatch, but I'm not sure what to do after that. Will she remain on the nest an extra week until it hatches or will she abandon it?