Just looking at this paper-wise I'm-a-readin':
* Minor children are spelled out in the decree
* The children's 18+ aren't part of the decree
* Any tax filing issues aren't party of family courtOption 1 - Go speedy next year
If you're using TurboTax, you can file before the opening date and TurboTax (Intuit) will cache your return and send it in as soon as the IRS servers open the connection in January 2018 for TY2017.
Some people even file with estimated numbers and simply amend their tax return later when they get the paperwork...all to be 1st!Option 2 - IRS route
* paper file for TY2016
* claim 18yr old
* IRS will tag it and send you back a communication on it
* then you send in the pre-2009 version of claiming the kids
The problem with this is that your decree doesn't appear (to me) to cover 18+, so the IRS might not agree. But this option hasn't appeared to be a huge mess for people.
* IRS doesn't agree, and they'll refigure your taxes without the 18-year old...meaning you'll pay the same amount as Option 1 this year
* IRS will agree and they'll send a letter to the Ex refiguring her taxes with a less-happy $$ number for her.Option 3 - sue the ex in small claims court
submit your proof as exhibits to introduce as evidence
dance before the judge (and hopefully do better than Chris Kattan did on DWTS
This option seems to make the least sense dollars-wiseOption 4 - bargain
Cut a deal with Ex that for the "off years" (when not claiming the younger kids), then the parents would claim the older child (or whatever deal you think might work)
As part of the deal, sign the IRS form Yeah...for my NJ-Ex....even if I wrapped up $1000 with a big bow on it, she'd balk at it and fight if she thought I was getting 38 cents out of the deal.
This is why a lot of people go for Option 1 and race to get that January return in