I'm very sad to have lost a chicken but concerne because I don't know why she died and it seemed to happen quickly. She's 7 months old, was laying regularly. I didn't really notice anything until about an hour before she died. Walking back to coop, she was lagging behind the rest. I walked behind her slowly to move her along and realizing she was moving so slow, I picked her up and carried her in. She did not peck at the scratch. Then 30 mins later, all the hens/rooster were in the coop roosting but my sick little hen was on the coop floor. I went out and she was listliss. I didn't feel anything stuck in her crop, her butt was clear. I couldn't feel any injuries. No sign of feathers missing. I left her and cheked again 30 minutes later and she had passed. Now, at the same time, my egg production went from 5-7 a day to only 3 today. Also, one of my hen's who is generally broody but leaves the nest when I take her egg, won't leave the nest. I pushed her out of the nest twice and she simply returned. She's sleeping there now. That was the least of my worries tonight. Any ideas what could strike so seemingly quickly and whether the other change in behaviors are related?