What to get my bestfriend for her 13th?

My bestfriend has her 13th birthday in a few months, but I have ABSOLUTELY NO IDEA what to get her. Her birthday is only a few weeks before mine, and she has already bought me a present. We sometimes tell eachother what we buy and she told me she got me pearl earrings and short overalls. Those are the two things that I adore the most, other than unicorns, but she never really told me what she really really likes, because she doesn't like favourites. She's really sporty and hates make-up. She loves JB but that's all I know. I thought maybe I could go something a little more personal..? IDEAS!!?!