Okay, here’s an idea: why not invite her peers to come along as well? Let them all have a “coming of age” party (without calling it that). With parental permission, and a big buffer of time on the front and the back for lunch and girl chatter (obligatory), it could be a memorable event for the whole group.
I’m thinking her 14th after she’s had a few sessions with me. But great idea. This is in a pretty conservative town so probably most of the parents would be okay with it.