She might like An Old Friend of the Family by Fred Saberhagen. It was written in 1979, so I have no idea how available it is. The protagonist is a teen girl whose great grandmother is Mina Harker. You can guess who the "old friend" is.
"The Bottle Imp" (short story) by Robert Louis Stevenson was good.
A sneaky way into history might be Ivanhoe (Scott) or The White Company by Sir Arthur Conan Doyle.
The Charles de Lint books (fantasy) might suit her. Jack of Kinrowan features a female lead and is a re-telling of Jack and the Beanstalk. Also, Tanya Huff might be good. You need to review Summon the Keeper to see if it's too adult for her. Not that it's Fifty Shades or anything, but it does mention adult feelings. I would have loved it at her age, but she isn't my child.
Call of Madness by Julie Dean Smith is the first of four.
Emergence by David Palmer has a very strong female teen lead. Highly recommended. It is science fiction.
SInce you like mythology, you might want to try her on the series by Tom Deitz, starting with Windmaster's Bane. The series stars in the Celtic mythos, then segues into Indian myths (feather, not dot).
Mr R highly recommends Shadow of the Lion by Mercedes Lackey.
I'm sure we can think of lots more. Some of these are out of print. You'll have to go to eBay to find them. Lets us know what you think, and we'll refine our search.