If he can't repay, the bank will blacklist your ID number, and it's not easy for you to borrow money from the bank yourself (mobile phone Baidu "Baidu cash loan", looking for the way to borrow money that knows you best). As for the money he owes the bank, you can ignore it. Even if the bank urges you through legal means in the future, the court will not take measures against you after reviewing it clearly. However, your life will leave a stain on the financial system. I suggest you urge your relatives to do things well.