I was browsing the shelves at Target with my 13yo niece a couple weeks ago and she had picked up the third book of the Crescent City series and immediately was interested. I've never read any SJM books but googling tells me it is certainly not for her age range.
I've only dabbled a little bit in the fantasy genre so I'm not sure what I can recommend for her that would be along the same lines, but more age appropriate.
She's started the Naturals series by Jennifer Lynne Barnes and she also just picked up the first book in the Percy Jackson series. Just to give an idea of other things she's into.
Any recs that you have would be greatly appreciated! Especially some we'd both enjoy because I'm trying to add more fantasy to my tbr. I'd love to do some buddy reading with her.
by TwistedSlinky