And nothing about a distribution from an IRA that you inherited from your brother ever goes on a Form 8606 inside of TurboTax. If your brother had basis in nondeductible traditional IRA contributions, you would have to prepare a separate Form 8606 outside of TurboTax to determine the taxable amount, then explicitly enter the resulting taxable amount into TurboTax when entering the corresponding Form 1099-R.
