Kelly Clarkson brought a very special guest onstage with her during her Hershey, Penn. show over the weekend, making for a unique addition to her set.

The star unleashed an impressive mashup of her hit “Walk Away” and the pop mega-hit "Uptown Funk” by Bruno Mars, and to help her in pumping up the audience, she invited out her adorable stepson, Seth Blackstock.

Clarkson revealed she’d been performing “Walk Away” for about 13 years and wanted to shake it up a bit with the mashup. The band started in with the instrumental intro for “Uptown Funk,” and Clarkson sang her tune overtop. Fans were clearly loving it as she launched into the “Uptown Funk” chorus. When the song’s breakdown hit, Blackstock appeared on stage with the background singers in perfect choreography with the others, leading half the audience in the “Uptown Funk” melody. The other half of the audience committed to sing “Walk Away.”

Blackstock was a natural on stage, performing with skill and pure enthusiasm. Perhaps another star is brewing in the Blackstock-Clarkson clan? It wouldn't be a surprise, given his lineage. Grandma Reba McEntire — Clarkson’s hubby, Brandon Blackstock’s, stepmother — thinks so. She posted a video of the boy’s rocking performance on Instagram.

The show was one of the first on Clarkson's Piece by Piece tour in support of the album by the same name. The pop-country singer will be on the road all over the U.S. and Canada with acapella group Pentatonix through October. Clarkson’s latest single “Invincible” was released in May as the followup to the album's leadoff single, “Heartbeat Song." The second single is currently climbing the Billboard Adult Contemporary and Airplay charts.

We're ready for that country album.

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