In the past week, I have had 3 eggs break in the nest. Based on shell color, they were from at least 2, if not 3, different chickens. Separately, I have a 2.5 year old barred rock who has laid 4 soft shell eggs from the roost at night over the past month. She typically lays 2-3 times a week, so this is roughly half the time for her. They have a high quality layer pellet (Vermont Organics layer) and free choice oyster shell. I can't tell how much oyster shell they're eating, as they seem to like to play in it-I often find it spilled out on the ground. As far as treats, they eat a little cooked corn and rice in the morning so they can have their probiotics, a few leaves of kale, and maybe an apple core. This is split between 8 chickens. They typically free range for 2 hours a day. What would you change for them? Should I consider some kind of liquid calcium in the water? Just wait it out?