I have a hen who just hit her 1 year old mark that recently (past month) has been laying thin shelled eggs.. I don't mean soft shelled, there is a shell that is hard but the shells break very easily. She has access to oyster as well as I feed back their egg shells crushed plus has calcium in their feed so unsure the cause of this or if I should even be concerned, as it is winter time and they have been cooped up frequently with the snow falls here in Michigan so not positive it's not just caused by stress of them all being confined off/on. She's an easter egger if that makes a difference. Sorry no pic but a pic would just look like a regular blue egg because as I've stated there IS a shell it's just quite thin. TIA.