Hello! I have a neutered male Mini Rex. He's a little over 2 years old. He is kept in an 8 by 5 foot pen indoors but he gets lots of supervised free roam time as well. He's fed 1/4th cup of Oxbow Essentials Adult Rabbit Food along with unlimited Timothy Hay and Fresh water each day. I noticed yesterday, he had a bit of urine on his tail so I took a damp cloth to clean him off. I lifted him up to make sure his tail was cleaned and I noticed a small white bump on his rear end. I will try to get a picture to add to this post. I'm really worried. He's eating, pooping, and acting completely normal. Is this something that will go away on its own or should I get him to a vet? Thanks!