Sorry, I should look at the IRS instructions for Form 8606 again, but I still don't understand why line 4 of Form 8606 would be blank in my situation. It "simply" asks how much of my line 1 non-deductible contribution was made between January 1 to April 15, 2019. I made the entire contribution for 2018 in March 2019, so the amounts on line 4 and line 1 should be the same, in my mind.
Why would line 4 be affected by distributions or Roth conversions from my own traditional IRA (when it is only asking about what portion of the non-deductible traditional IRA contribution was made between January 1 to April 15, 2019)?
As I mentioned, in March 2019, after making the non-deductible 2018 contributions to our traditional IRAs, my wife and I did roll them over (which I assume is the same as converting) to our Roth IRAs (as 2018 contributions).
I'll have to look into what you wrote about calculating the taxable amount of distributions from the IRAs inherited from my parents on a separate Form 8606 prepared outside of TurboTax and entering that amount into TurboTax. Where in TurboTax would one enter that? Does TurboTax give instructions on this? If I had correctly identified the distributions as from inherited IRAs and not calculated and entered the taxable amount, I guess you're saying that TurboTax would have failed to include that amount in my tax.
