Luke knew it was the girl's birthday because she was holding a sign in the concert crowd. "Let me drink a beer on stage with you. It's my 21st birthday," the sign read.
That''s when he agreed. The cute moment didn't go off without him performing his adult civil duty. He carded her!
"I need to see your ID. You'll have my a– going to jail tonight, you know that?" Luke said while her friends searched for her card. "I don't know, that kinda looks fake to me, but I'm gonna have to trust ya."
Luke's team scrambled to find two beers, but they came through. "Damn, you look 16, but I guess you're 21!" he added before singing a short, funny, version of "Happy Birthday." They shared a few sips of the booze together, then she went back to her seat with the best 21st birthday party story ever.
This isn't the only sweet thing Luke's done lately. He just took in his orphaned nephew after the boy's father, Luke's brother-in-law, passed away a few months ago. You can read about that, here.
Watch Luke and his fan get their drink on together in the video below. It's just another reason why we adore him!