She is currently taking summer classes (rather than working in the summer!!!) and I'm not sure how she financed it. I worry she may have signed my name for me, but I hope she wouldn't do that (these loans have never shown up on my credit report--is that normal?)
I think the only way to do that would be to ask her.
I don't think I've ever been in the position to lend a large-ish sum of money. Neither of my siblings would approach me, preferring to deal with each other or my parents. Probably because I'll give them my (un-asked for) opinion as well as the cash.