Rather than typography, which is many levels of understanding removed from the basic idea of letters-as-symbols-for-sounds, teach her the basics of calligraphy, from which all typography is derived, after all.
We learn, and (hopefully) teach, any subject using gradients of understanding; reading and writing are no exception. If a child doesn't grasp the correlation of letters to sounds, for example, she won't really understand why we have letters in the first place so will never learn to spell. You'd probably be astonished how often that exact point comes up in teaching adults to read.
Unless she has the basic letter forms down pat, she'll be confused by the niceties of italic vs. roman or copperplate vs. block letters, never mind terminals, bowls, aperture, x-height and the rest. That would be like trying to teach calculus before arithmetic.
A student of typography who doesn't understand the origins of type in brush and pen lettering will never really "get" the concept of axis or different types of serif. How would you really understand what a terminal is if you never learned that it was originally the end of a pen or brush stroke?
Calligraphy was around long before type, and type was originally designed to imitate calligraphy. It really wasn't until the machine age of the 18th Century that the first typefaces that weren't derived from handwritten text were created.
I would recommend a good, simple text and exercise book of calligraphy, and a set of nice pens. If she lights up at the idea of beautiful lettering, you'll not have any problems with teaching typography later.