Hey there everyone, I have read and read about the possibilities of what is going on with my bird or birds and I still cannot figure it out. So I am reaching out to this community to see if I can get some ideas from the experts. The main issue is that I have one hen who has been seeming sick on and off. She suddenly sits with her head tucked in and her tail down. This happened for the first time 3 months ago. She is the top of the pecking order but did not roost with the others and tucked herself away under the nesting boxes to sleep. The next day she seemed fine and was back roosting with the others. Recently, I have noticed her, again, tucking her tail down and head in. It is not a constant thing though. She will act completely normal when she is free ranging but when in the run or coop she will show this same posture of head in and tail tucked. A few days ago, I noticed something very gross in the nesting box with other eggs, it turned out to be a lash egg. I did not know who laid it until yesterday. I found my "sickley" girl, who had been acting ill that day, trying to lay an egg, it was a meaty fleshing thing instead. So I know it was her who laid the lash egg. So, I am trying to figure out what is causing her to be sick and how do I know if it will spread to my other birds? I have read about salpingitis, infectious bronchitis and thought about those both being potential cause. However, the rest of my birds do not seem to have any symptoms. Here is the main info about my chickens: I have 6 hens and I get mostly 4 or 5 eggs a day All of my hens ( including the sickish one) have a bright red comb. My hens are almost 2 or year years old but I do not know for sure because I got them from someone who said they were 1 or two years old when I got them and she did not raise them as chicks. I do a deep litter method in the coop with straw I have not de-wormed by chickens since I had them in this past year. all other chickens seem healthy with no sneezing or coughing. We did have a bought a few weeks ago of some eggs with thin shells and soft points. I increased calcium and haven't had those issues since. We have had a fox lurking very close to my girls ( I had to chase it away once) so they could be stressed. Info about the sick chicken: Seems to be foraging and eating fine Tucks head and tail in a lot lately when in coop or run has laid two lash eggs has been checked for sour and impacted crop and seems fine poop seems to be frothy or runny and vent is messy So, what do you think and what would you do? I really appreciate any help.