Deformity?

So her vent is a large hole? Sorry- its hard to imagine how bad it could be without pics. I would let her continue on if she's eating, drinking, and pooping normally. If she lives with other chicks you should watch very close to make sure she isn't being picked on. If she does start to develop problems I would cull. Good luck with your decision, and sorry your first post had to be about a problem with your chook. You should definately check out some of the other sections and make a few more posts. When you get to 10 posts you'll be able to put up pictures, which would really help to see what's going on with your baby and how bad it actually is.