I have an Easter egger who consistently lays soft shell eggs. She is a great layer and consistently lays eggs, but they are always soft shelled. Sometimes the shell is so soft the shell crumbles when I pick it up, sometimes its rubbery, but most of the time it breaks in the egg box right after she lays. Is there anything I can do for her?? She does have access to oyster shells at all times. Thanks for any help.