Supernatural's Castiel will have a major storyline with his vessel's daughter during season 10.

'Supernatural' Season 10 Premiere: What To Expect From Dean, Sam & Cas In 'Black'

Cas (Misha Collins) chose Jimmy Novak as his vessel back in season four, and the loss of her father sent Claire Novak's life in a downward spiral. An ailing Castiel will reunite with the 17-year-old in the upcoming season, and Claire may be vital to his recovery.

Last seen in season 4's "The Rapture," Claire is now described as a "punk-rock-pretty" foster child who has been in and out of homes since the disappearance of his mother. Momentarily Castiel's vessel during "The Rapture," Claire may still carry a trace of the angel's original grace. Just like Cas extracted Gadreel's residual grace from Sam (Jared Padalecki), perhaps he can do the same with Claire.

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"We're very excited about the season-long arc we have for Castiel," said executive producer Jeremy Carver, according to Zap2it, adding, "Claire Novak is very much an important part of that."

Find out more when Supernatural returns to The CW on Oct. 7 at 9 p.m. ET. Click the video below to see a preview for season 10.

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