I recently came back from vacation and my friend was watching my hens. One was recently exhibiting stand-off behavior where she would stay in a corner all day and not eating as much by their accounts. Then she started behaving normally. I returned today and saw them for the first time in a month. Her vent (butt?) features a big red ball (size of an egg or bigger) under her tail. It looks like she recently molted too as she has some of the fuzzy feathers falling out and new spines coming in. I don't think it's an impacted egg because I've read they typically die if the egg isn't removed within two days and she's been like this for several weeks. Also, she is the one hen that used to sleep in the nesting box (started about 3 months ago and stopped doing it last month) for a period and her butt is very "poopy" because of this. I was thinking infected vent because of this. Recently my friend told me she has diarrhea too, but it didn't look bloody I'm disappointed that I wasn't alerted to this earlier, but are any of these signs making anyone think egg-bound, worms, infection, etc? thanks in advance If I need to, I can bring her in the house in a dog crate and monitor her.