It depends. Whose name and social security number appear on Form 1099-MISC. If the Form 1099-MISC is in your brother's name with his social security number, you wouldn't report that on your return. Being that he has been gone for 20 years and does not have a filing requirement then the 1099-MISC would not be reported.
If the 1099-MISC came in your name and social security, it should be reported on your tax return.
Based on the comment you received from the TurboTax return, it does not need to be reported.
