Congratulations are in order for Garth Brooks‘ youngest daughter, Allie Brooks — she’s newly engaged! The 21-year-old’s handsome beau, Jonathan Roberts, popped the question to Allie at Garth’s LA concert on Friday, July 28.

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Allie and Jonathan were attending the country star’s latest show to celebrate her 21st birthday. First, the young lady surprised concertgoers by appearing onstage with her famous dad to adorably sing a few of his hit songs as a father-daughter duet. Then, Garth got the huge audience to sing “Happy Birthday” to his girl — so cute!

When Allie returned backstage, Jonathan was waiting to sweetly give her a hug and kiss. But then, he suddenly dropped down on one knee and asked the aspiring singer to marry him! In a video later posted to Jonathan’s Facebook page, an astonished Allie can be seen covering her mouth in disbelief before exclaiming “Yes!” and sweetly embracing her new fiancé.

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“Wow! LA was incredible. It’s definitely gonna be one to remember — from two amazing concerts to jet skiing 40 miles up and down the coast. We Celebrated Allie Brooks’ birthday! Also, she said YES! I’m beyond blessed to have this beautiful woman in my life. She’s anything but typical. She’s so unpredictable,” Jonathan — who works as a physical education teacher in Nashville, TN — wrote on his Facebook page following the exciting proposal.

Allie is one of Garth’s three daughters with his ex-wife, songwriter Sandy Mahl. The “Friends in Low Places” singer — who was married to Sandy from 1986 until 2001 — is also a dad to Taylor Mayne Pearl Brooks, 25, and August Anna Brooks, 23. Following his divorce from Sandy, Garth tied the knot with country star Trisha Yearwood in 2005.

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In a previous interview, Trisha — who doesn’t have any children of her own — candidly revealed she was “scared” of Garth’s three kids before they got married. “It [was] scary. I’m madly in love with this guy, and this is the deal. So, I was really scared of them at first,” she said back in 2007. “We would have them every other day, so they would go to their mom’s at 6 o’clock, and I would be sitting there thinking, ‘What do we do until 6 o’clock? I don’t know what to do with children.’ [Then] it became, ‘Okay, I’m still scared, but it’s not as bad,’ and then it became, ‘I love having them all the time.’ You fall in love with them. You learn why people have kids.”