The country rocker son of Waylon Jennings was performing in Utica, New York, when he stopped the show to ask the actress to marry him.
A concertgoer tells People.com, "She (Drea) was dancing on the side of the stage holding (the couple's 18-month-old daughter) Alabama when he called her onstage.
"She was so surprised by the proposal."
The couple has been dating since 2001.
Jennings confirmed the news on his Twitter page blog after the gig, writing, "Asked drea to marry me on stage tonight. I'm a lucky man."
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