Kane Brown's set in Philadelphia over the weekend (part of Chris Young's 2018 Losing Sleep World Tour) included two unannounced special guests.

Before he launched into his hit single "Heaven" — his second-ever No. 1 — Brown invited two young fans onstage to help with vocals. The concert took place at Philly's Mann Music Center on Saturday (Sept. 29).

"Don't be shy now, come on! Dance!" the country star told the boys — and they obliged.

The Real Story Behind Kane Brown's "Heaven"

Brown shares his mic, giving each child a turn to belt the lyrics into the mic, much to the crow'd delight. The boys seem to be big fans of the country star, because they know the song verbatim. A big smile encroaches on Brown's face, clearly impressed at the impact of his music.

While Brown's past singles prove to be hits in concert, the singer is laser focused on his new music. He recently dropped a summery throwback tune called "Short Skirt Weather" on Sept. 27. "Oooh, my baby's made for short skirt weather," Brown croons in the chorus of a bubbly song about women in miniskirts. The song is from his upcoming sophomore album, Experimentwhich will be released on Nov. 9.

In January, Brown will embark on a headlining tour that features openers RaeLynn, Danielle Bradbery, Granger Smith and Jimmie Allen.

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