I have an 18 mo old EE hen, Flag, who has never given me any trouble. She started acting Lethargic last Monday. She didn't want to leave the coop with the other girls and when I prodded her to get her out, she just wandered around slowly by herself. Her comb looks red and normal. Her poops look normal though she does have some white residue on her feathers (but so does one of my BR). She doesn't have mites or lice. I've never wormed them but use DE around the coop and their bath and regularly inspect feces. I've not seen any evidence of worms. All my other hens are just fine. She seemed a little better on Tuesday. On Wednesday, Flag laid a pretty egg and started acting normally again. She usually lays every other day and Wednesday's egg was the only one she's laid this week. Today, she refused to leave the roost. I just brought her some yogurt and she ate 2 bites. I felt her abdomen and it feels like it has fluid in it. I just had to cull a BO I got at the same time as Flag for Egg Yolk Peritonitis. She hadn't laid an egg in 5 months. My question is, is it possible for her to lay internally then lay normally like she did on Wednesday? I'd really hate to have to cull another bird. I can't help but wonder what hatchery the feed store got their birds from. I bought 3 chicks from them last April. One died after 2 weeks, the other was the BO I just culled last weekend and now Flag.