Our only EE hen has just started laying so far 2 lovely green eggs But.......both have had a small impact type crack? Shells on all are nice, and no one else has had crack issues. Is it a new layer thing? I have lots of hay in the nest area, but they move it and lay on the wood. and of course all in the same spot, but they almost always take turns. Any ideas on how to stop the cracking? I love my green eggs!!! Thanks!