I decided to bathe my 5 month old Silkie pullet because her vent feathers looked a little dirty. While bathing, I noticed a walnut-sized lump distancing from her bottom. To be clear, her vent is perfectly fine and she is pooping regularly. Poop is moderately well-informed with some urates. I thought she had a big bump of poo stuck to it, but it didn't budge with soaking and gentle massaging. She doesn't seem to be tender on or around the lump! I dried her off and let her stay inside for the night (since it is cold out). She had no trouble settling down for sleep and waddled right up to the food and water in the morning with the other girls. Should I worry??