Elsa and Anna's parents were only featured at the beginning of Disney's Frozen, but they will likely be explored further in ABC's Once Upon a Time this season.

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With the introduction of the world of Frozen to Once Upon a Time, viewers will get to learn some backstory on Elsa (Georgina Haig) and Anna's (Elizabeth Lail) past as well as their parents.

"There may be some things with the parents we didn't know about pre-Arendelle," executive producer Edward Kitsis told TVGuide.com in a new spoiler report. It is not clear if viewers will be introduced to Elsa and Anna's parents, though it at least seems likely that they will be touched upon in some way via flashback.

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The new season will presumably take place after the events of Frozen, with Elsa escaping from the urn in which she was kept in the Season 3 finale.

"What happened to her to get her into that urn and what was going on in her life at that point is what's going to be revealed and what's going to be pushing the story forward," fellow executive producer Adam Horowitz added. "Hopefully you'll find that there will be some cool surprising connections between Arendelle and our world."

Once Upon a Time appears to be heavily banking on Frozen in Season 4, with the inclusion of Elsa, Anna, Kristoff (Scott Michael Foster), Hans (Tyler Jacob Moore) and elder troll Pabbie (voiced by John Rhys-Davies).

Once Upon a Time Season 4 is set to premiere Sunday, Sept. 28 at 8 p.m. on ABC.

Tags: Once Upon A Time television ABC