My 17 year old son has $8,500 in investment income, so he has to file a 8615. He also has $8,250 in deductions, so his taxable income is $250 and he owes no tax. I am getting an extension because I want to see how my Roth conversion plays out; unless it goes up significantly I will likely recharacterize half of it. I put both scenarios into to the 8615 and he doesn't owe any tax either way, so in a reasonable world it would not matter; but I am concerned about his return and mine not matching up which might happen if I file his now instead of waiting until I file mine. Is this a legitimate concern, or am I overly paranoid about the IRS?
Yeah, it costs nothing to get an extension for him, but I have a bit of OCD (you probably guessed that...) and I would be much more comfortable to get the darned thing out of here.