Garth Brooks serenaded his daughter Allie on her 21st birthday, but a surprise engagement made her night even more memorable. Her fiance shared video of the magic moment.

It all happened at the Forum in Los Angeles on July 28. Allie was backstage when boyfriend Jonathan Roberts dropped to a knee. Watch as the 21-year-old bursts into tears, says yes and gives him a great big hug as her father is on stage singing "She's Every Woman." Roberts is a physical education teacher in Tennessee. Watch it go down:

That moment was separate from Brooks' onstage serenade. First Dad recognizes Allie a as a great songwriter, acoustic guitar player and singer — someone he's been singing with since 1996. Then he leads the crowd in singing "Happy Birthday" to his baby girl. She's surprised, and maybe a little embarrassed. But she's also preparing to sing on stage with her dad, so she's focused.

The "Ask Me How I Know" singer has three daughters, including Taylor and August. He's also a two-time grandfather, with August giving him two granddaughters in recent years. Allie is the one most interested in singing. Earlier this year she posted an acoustic cover from her bedroom, singing her father's "She's Every Woman" in a tender recreation of the hit.

Brooks' tour has offered surprises at seemingly every concert. Marriage proposals, baby gender reveals and free college tuition are just a few of the jaw-dropping, non-song highlights from his world tour. He's set to wrap the North American leg in 2017 and has hinted that he plans on traveling to Europe and beyond in the years to come.

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