It could only be possible if your parents or a parent was a representative payee for your brother. The representative payee is held accountable for benefits paid. They are responsible for notifying Social Security that the person they represent is working.
I would like to add that your parents can file for a waiver of the overpayment. In order to file a waiver your parents would have to provide their financial information. Financial information is used to determine if the repayment amount can be reduced. If your parents were not your brother's representative payee, they need to contact Social Security. If your parents go through the waiver process they will be entitled to a hearing as well. An administrative law judge might determine that they owe nothing or a very low repayment amount. I would suggest filing a waiver and going through the process until they get a chance to see a judge.
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Social Security Disability
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