When asked about whether or not City of Heavenly Fire and Clockwork Princess would have extra content this is what she had to say:
I don’t know about Heavenly Fire yet, but as for Clockwork Princess, if you’re asking if there will be different editions with special content like letters — no. In every first edition of the North American version of Clockwork Princess, there will be a family tree that shows the connections between the generations in The Infernal Devices and the generation in The Mortal Instruments.
It’s pretty cool.
** First edition: A publisher prints a certain number of books. It is called a “print run.” When all those books are sold, they print a new run of books. Each print run is numbered. The first edition is every book from the first print run. How do you get a first edition? Your best bet is to pre-order the book. You can do that online anywhere that you can order books, or go into any bookstore and pre-order.
*I don’t know about its availability overseas yet.
Alls I know is that I have already pre-ordered my copy so I am good!!!