I have a question about itchiness. Iris always wants us to scratch her tail. Now, neither of us know exactly how to describe her tail, but it's kind of like a nubby-type of situation. I would guess it's a typical Boston tail. Anyway, it is always irritated and itchy and she's always sticking her butt in our face so we'll scratch it! Any idea what's happening here? Is there any way to get rid of the irritation? Sorry if I sound a little clueless, but it does seem to be bothering her a lot and I want to see if we can help her out.
A few pictures...
Lily, making a face:

Iris and Lily:
Thank you!