My beautiful Birman is chewing his tail bald. Help!

Dear Most Esteemed and Knowledgeable Kitties:
First of all, thank you very much for your site. I recently adopted 2 kittens (brothers born June of this year), and these are the first and only cats I’ve ever had. I’m one of those “I’m-a-dog-person-not-a-cat-person” people, so I know nothing about cats. I’ve learned so much from your [...]