Hi. I'm really new at this and need a little help. I have a hen that decided to go broody about 15 days ago. I convinced my mom to leave her alone and let her sit on the eggs and try to hatch them. Well, I started searching the internet for information about what you should do and curiosity got the best of me. So, I candled all the eggs Saturday night. One problem, I don't have a clue what I'm looking for, Ive looked at the pictures on the internet but its just not the same. MAIN QUESTION: Has the egg gone bad if there is a large air sac at the top of the egg and the rest of the egg is completely dark? Only in 2 of the eggs am I confident that I saw movement. I'm also not sure when she started brooding so I don't know how old the eggs are. Plus I just realized that she has been stealing eggs and adding them to her clutch so no telling what days all the eggs are on. I was never planning on reproducing from my own flock but now I have gotten my hopes up and really would love to get even just one chick. I know that there is a good possibility of the eggs being fertilized and growing because somehow I got an egg the other day that when I broke it open, it had about a 12 day old developed chick in it (I was really upset).