Mariah Carey Turns 'Mean' in Her New Movie 'A Christmas Melody'

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ET was on the set of the Mariah Carey-directed TV movie, A Christmas Melody, which the GRAMMY winner also stars in! Find out what she said about being on double duty.

"It's a lot to handle the dual responsibility," Carey told ET. "It's not easy, you know what I mean?"

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The holiday movie revolves around Kristin (Lacey Chabert), a beautiful, stylish single mother, who is also a talented clothing designer. At the beginning of the movie, Kristin has just had to close her small Manhattan boutique to return to her Ohio home town and live in her parents' former home. It's an adjustment for Kristin and her daughter Emily - especially when she runs into her former high school rival Melissa (Carey), who tries to make Kristin feel as unwelcome as possible.

Chabert praised Carey's demeanor behind the camera.

"She's a very relaxed director," she said. "She definitely knows what she wants and has a great point of view, but she really lets you go and just do your own thing."

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Perhaps the best example of Carey giving her performers the space to be creative was in 10-year-old Broadway star Fina Strazza's rendition of Carey's 2010 hit "Oh Santa."

Watch the video to hear her version of Carey's Christmas hit.

A Christmas Melody debuts Saturday, Dec. 19, at 8 p.m. ET/PT on Hallmark Channel with Mariah Carey's Merriest Christmas immediately following at 10 p.m. ET/PT.