My two Khaki Campbell hens, Daisy and Minnie, have been laying soft eggs in the evening. This has only happened three times in the past week and they only started laying about three weeks ago. Is this normal or should I be concerned? Their diet consists of duck crumbles, lettuce, fish and lots of worms (we go worm hunting at night.) They forage and have mud to eat. I just started to supplement with oyster shell, but when they lay in the mornings the eggs are normal. We also have a drake, Jack. Thanks!