Alright, I got a bit more, though it's not too much. On 7/1 (mo/day) she came over to my house, and her 3DS got a few streetpasses, but basically sat on the table for the day. It got dropped when she was leaving, but it fell onto carpet and the drop was only a few inches. She took it home, played on it for a bit (About an hour), and powered it off. On the following Monday (7/3) she told me that it was acting weird and that the screens had stopped working.Please do that, though I think custom firmware and ntrboothax are the only saviors for her 3DS now (unless she wants to hand Nintendo $70+)...
I got to see it again last Saturday (7/8) which is when I tried the troubleshooting stuff on the guide, and making this thread before telling her that it got bricked. I did look at the inside of the system to be sure nothing had come loose or disconnected, but that was after trying the troubleshooting steps.
To summarize: A few days before it bricked, it had little use and a small drop.