Edward Kitsis and Adam Horowitz, the co-creators of ABC's Once Upon a Time, recently spoke on Emma (Jennifer Morrison) and Regina's (Lana Parrilla) friendship and how it has evolved through this season.

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Emma decided to join Operation Mongoose to help Regina and Henry (Jared Gilmore) search for the Author in the midseason premiere of Once Upon a Time. While Regina was naturally guarded about this and her entire friendship with Emma, the co-creators told The Hollywood Reporter that their relationship will probably change.

"Regina hasn't been that open to that friendship, but I think that's going to change," Kitsis said. "I think the natural evolution is fun for us, because I think [in terms of the show] Regina and Emma is a huge part of it. It started with [Regina] trying to get her out of town, and they've fought together, they've fought against each other, and now whether they can be friends, I think we're going to see in the second half."

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Horowitz also said that Emma and Regina have that shared bond that will help bring them closer together.

"I think also, given what Emma is starting to go through and given what Regina has gone through ... in addition to Henry, they'll have something else they share," he said.

It remains to be seen if Emma and Regina will come together as friends in the final episodes of season 4, but fans of "Swan Queen," as they are affectionately called, are certainly hoping for it.

Once Upon a Time airs Sundays at 8 p.m. ET/PT on ABC.

Watch the promo for the next episode of Once Upon a Time here: