What can we do so that my parents don't have to pay my brother’s debt?

Your question does not clearly indicate what has occurred. If your parents are not responsible, then dispute it with a vengeance. If the creditor is simply trying to bully your parents into paying your brother's loans, your parents need to clearly express that they are not responsible and ask to be left alone. If the creditor continues to harass them, then debt collection or other consumer claims can be pursued with legal representation. If they are, on paper, "responsible" because of fraud committed by your brother, they need to assert that and have it investigated by the creditor. They should request copies of the promissory notes or loan guarantee documents containing their signatures. Then, they should deny the validity of those documents. If, however, they did take out loans, co-sign or guarantee for your brother, then they will have a difficult time. Bankruptcy is usually the first thought that is considered, but student loans are difficult to discharge, even when the loan relates to a child. A bankruptcy attorney can take a look, but the expectation would be that your parents' responsibility would not be dischargeable unless their circumstances are extraordinary. If there is any point, such as your brother having left assets behind, your parents could consider a lawsuit against your brother to get to those assets through a judgment.