One of my girls had some crusty frozen feathers on her hind end (we are in Wisconsin so cold here) and I thought it looked red. I brought her in and used warm water and a washcloth and cleaned up her feathers and then dried her before taking her back out. But this spot is red and I don't know if it is swollen or if this is normal sized. She didn't squawk or flinch when I touched it and it doesn't feel hot or have any spot that it oozy. Could it just be irritated from the yucky feathers that are now cleaned up? She is on the nest and laying daily yet, at least I am assuming so as I see her on the nest daily and later there is an egg. It could in theory be others after her, but most lay before her and u get those eggs up right away. Usually she is my later morning layer so when I check around noon after she has been sitting and there is an egg.