Got this one the other day. We have a small Polish mix hen that started laying the day we brought her home. She usually lays a medium sized egg, about every other day or so. One day last week she left this one behind: I wish I had one of her normal ones to compare to. There was a small hole pecked in one end, almost like she was trying to break it to get it out?? There was nothing leaking out of the egg, so I figured either it could be an egg within an egg, or the membrane wasn't broken. We took it inside and cracked it right away.... This is our second year with chickens, first double yolker!! And I'll never eat store bought eggs again!!