Spoiler: They go way back to before Reba was Clarkson's mother-in-law.

Kelly Clarkson and Reba McEntire
Credit: Kevin Winter/ACMA2013/Getty Images

Long before Kelly Clarkson and Reba McEntire became related through marriage— Reba's stepson, Brandon Blackstock and Clarkson wed in 2013 — Clarkson looked up to the iconic red-headed country star.

As Country Living recently pointed out, the musical greats actually crossed paths long before they were acquainted at family gatherings. In fact, the twosome first met when they performed together at a concert in 2002, the year Clarkson won American Idol.

"This is the first time I sang with her. We did ‘Does He Love You,'" Reba tells Country Living in a video interview. "They told her when she won the very first American Idol that at the finals she could sing with her idol, and she chose me. So that's the first time we got to meet. Little did we know we'd be relatives, we'd be in the same family."

You can actually watch the duet on YouTube here, to which Clarkson prefaces the performance: "One of my inspirations from when I was a little girl, I have every record of her...Please everyone welcome my American idol, Reba McEntire."

"I am so proud of you...I gotta tell you, I am so happy to get to sing with you tonight," Reba says, adding, "but in the song we're gonna sing, you stole my man and I'm not happy about that!"

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These days, Reba is a loving mamaw to Clarkson's and Blackstock's kids and we're sure there's plenty of impromptu songs belted out around their very musical family table.