Hello all- Please help if possible. We are new to chickens - Long story but we swapped out a cockerel for a pullet and were given advice to keep her with the other pullets in the run, while she is in a crate and at night put her in the coop with them. This happened for the past 2-3 days. Yesterday I noticed she was sneezing a few times but seemed otherwise OK. Tonight her breathing is rattling, almost like someone with bad bronchitis or pneumonia, and she has a lump on the left side of her chest. There appears to be some yellow discharge coming out of her nostrils but otherwise she seemed OK. We have her in a dog crate now with blankets for the evening and gave her water with probiotics and electrolytes which she quickly gulped down. What could this be and how can we help her if possible? Of course we are also worried about the rest of our girls who are the same age but they seem OK for now. Any help you can give would be much appreciated. Thank you!!