I have a broody Australorp, sitting on 4 fertilized eggs (that I purchased). She voluntarily moved from the popular nesting box to one on the ground (I tricked her with fake eggs, before I got fertilized ones). But I found 4 extra eggs under her. I don't know how they got there, because they all like laying up top (like 4 ft up in the nesting boxes.) Anywho, the point of this - after I removed the unfertilized eggs, I found that one of the fertilized eggs felt a whole lot lighter than the others. Like empty feeling. I'm guessing that's bad? This is my first go at this.