Lana Parrilla recently spoke about how her Once Upon a Time character Regina has regrets over not killing her sister.

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Parrilla appeared at Comic-Con over the weekend alongside many of her Once Upon a Time co-stars. She spoke with several critics, including Blogcritics, about how Regina feels heading into season 5.

As fans know, Regina is in a bit of an awkward situation with sister Zelena (Rebecca Mader) who disguised herself as Robin Hood's (Sean Maguire) wife Marian (Christie Laing) and got him to impregnate her. This obviously caused conflict considering Robin is supposed to be Regina's true love.

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"I think Regina already regrets not killing Zelena," Parrilla said. "But there's already been so many rewards when she's done the right thing... Deep down inside, she knows it was the right thing to do. So it's all going to come with challenges going forward, but I don't think she feels threatened by Zelena at all."

But Regina will be preoccupied with trying to rid Emma (Jennifer Morrison) of the darkness inside her.

"Regina really hates the fact that Emma has done this because now Regina has to do something about it," Parrilla said. "I think she really hates owing someone. It's become a burden, and something she had to do something about, but if anyone can relate to where Emma is in this new incarnation, it's Regina. She's been there."

Parrilla added that Regina will be in a new leader role as she and son Henry (Jared Gilmore) lead the charge to help Emma.

Once Upon a Time season 5 premieres Sunday, Sept. 27 at 8 p.m. ET/PT on ABC.

Tags: Once Upon A Time television ABC