Editors' pick: Originally published Feb. 14.

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There is a reason that Modern Family, the ABC show about nontraditional families, is in its eighth season. 

Not only is it funny; it's the new norm.

The so-called traditional family, with a mom, dad and 2.5 kids, is basically nontraditional

"So much has changed, we actually changed the name of our practice," says Janis Cowhey, partner at the tax and accounting firm Marcum and co-leader of the newly named Modern Family & LGBT Services Practice Group.

And these days, the modern family actually may have more complicated tax issues than same-sex couples.

Thanks to the landmark case Obergefell v. Hodges, decided back in June 2015, all states now are required to issue marriage licenses to same-sex couples and to recognize their marriages from other jurisdictions.

So now same-sex couples are considered married filing joint like the rest of the married folks.

Thank goodness. So now that's easy.

Tax issues can occur, though, if the couple decides not to get married, but instead become domestic partners or be in a civil union.

The federal government doesn't recognize either of those situations as a legal marriage, says Annette Nellen, director of the graduate tax program at San Jose State University

But some states do.

For instance, California considers domestic partners to be married. So the members of that couple would have to file their federal tax returns as single people but their state return as a married couple, says Nellen.

Given the complications, it is important to talk to an expert who knows your state.

And pay attention to your forms. 

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