One of my girls laid a strange egg and Im afraid because one of her sister mates died suddenly last week for no apparent reason. There was an olive size and color sac inside what looks like a healthy egg. It was gross, at first we couldn't puncture it because it was so slippery and than when we did this funky greenish stuff came out, the cord was also attached. Could it have been a double yolk that didn't take, or an old egg that got attached to a new one??? I have a picture of it , can I post it?