I have had my sebright hen since monday and on tuesday she laid an egg in the middle of the run. shell was fine and she ignored it. Tried to put it in nestbox to show her where to lay but she pushed it back outside when I wasn't looking. Today I was gone for an hour and came home to fine 1/2 of an eggshell in the run. There was what looked like the white part next to it but no sign of the yolk or other 1/2 of the shell. shell seems thin and brittle compared to the other one. She is acting fine and I got her layer crumble but when I got her I only had starter, my others aren't laying yet and local store was sold out of layer. Did give her yogurt to help make up for calcium and will get her the oyster shell as soon as I can. Could she/they have eaten it? She is isolated with 1 other hen and the roo, all buff sebrights. only one of the hens is laying, the other is a little younger. Should I worry? What signs should I look for that the other 1/2 may be inside her? She is so small I worry. I look forward to any advice as this is my first experience with an egg laying hen.