England's Glastonbury Festival is already a popular five-day music festival, but this year, it got even cooler. Dolly Parton played the event on June 29, and she had quite a special guest join her for a surprise duet.

Parton invited the legendary Richie Sambora -- the longtime lead guitarist of Bon Jovi -- to join her on stage during the festival.

"Here we go, you sing along with us," Parton told the crowd in England. She wore a white sparkly outfit with crystal accents and tassels and was all smiles during the performance. She kept her hands free and sang through a headpiece so she could clap and freely move about.

Sambora, on the other hand, brought the rock 'n roll to the stage as he played guitar on their duet. He donned a black hat, aviators and a black vest. The T-shirt he wore under the vest was a special tribute to the lady next to him -- her face was plastered across it.

Together, the artists played a song that Sambora penned for Bon Jovi, 'Lay Your Hands on Me.' But Sambora wasn't just there to play the guitar -- he also joined Parton on vocals for the song.

The unexpected collaboration ended with a warm hug and a huge thanks from Parton to her friend.

"Thank you so much," the country icon told Sambora. "What an honor. What a thrill this has been today. Thank you so much for being so kind to us."

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