If she "might" return it then it sounds like a gift and not a loan with a loan agreement. To be a loan the receiver must have a binding legal obligation to repay it. The receiver of a gift, no matter how much, does not report it anywhere or pay any tax.
The giver of a gift that exceeds $15,000 to one person in a year must file a form 709 gift tax return. There is no tax to pay, but the gift will reduce the lifetime $11.58 million dollar exemption amount.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
