About a week ago, I saw our Speckled Sussex hen, Kitty, suddenly stop in the middle of the lawn, and adopt a stance that looked like a little owl. A few moments later, she laid a smallish egg that had a paper thin shell. While odd, I thought maybe it was one of those fluke things and she was just squeezing out an extra egg that didn't have time to form a full shell. Today, she was standing up on the picnic table, and the same exact thing happened! She discharged about a teaspoon of clear liquid with a few hints of wispy white matter before laying the egg. I had been taking photos of the chickens, and so had my camera ready. Owl stance from the back. A few moments later! The odd egg next to a normal egg from an EE hen. The shell depressed from the pressure of my fingertips, it was so thin! She is the only hen doing this (that I'm aware of). They are fed Blue Seal Egg Maker Crumbles, and get occasional treats - usually fruit or veggies, and a hand full of BOSS. They get to free range in the evenings about 4-5 times a week. They've been getting quite a few Japanese beetles. Oyster shell is available all times from a little hopper. She acts fine other than the odd egg. She went right back to free ranging without a care in the world after she laid it. Does anyone have any idea what may be going on?