I have to rub her belly to help her, because she gets to where she can't hardly walk or stand. Today she laid an egg and the shell was so thin it was cracked open on one side and had a small opening on the other side. This is the first time this has happened since she started laying. Can someone tell me what I need to do for her and how to improve the egg health? She only weighs maybe a pound she smaller than a Cornish hen.