Miley Cyrus shocked audience members of a charity concert in Nashville, Tennessee this past weekend but rocking out on stage alongside country star Jeffrey Steele.

Steele hosted the event in memory of his 13-year-old son Alex, who was killed in an all-terrain quad bike accident last year, to raise money for charity.

And the singer was just as shocked as the crowd when 15-year-old Cyrus appeared on the stage, asking to sing a duet with him, according to People.

The pair performed hit track Simple Song, which was originally recorded by Cyrus, and was the only song written by Steel that appeared on his son Alex's MP3 player when he died.

And after a second duet, a rousing rendition of Steele's Hollywood Girl, the country singer paid tribute to Cyrus, telling the crowd: "Miley might live in Hollywood, but in her heart, she'll always be our Tennessee girl."