At your discretion, missed payments can be reported to the credit bureaus. This can create an incentive for repayment. At the same time, successful repayment of loans can help your family build credit.
In addition, you can elect to have future gifts placed on hold until and unless repayment is in good standing, or full and complete. In the case of delinquent loans, you can elect to have remaining cash donated to charity after a period of delinquency.