Green Day’s Billie Joe Armstrong Fulfills Autistic Teen’s Dream Onstage at Riot Fest

A chance encounter became special when Green Day's Billie Joe Armstrong spotted a teen in the crowd at Chicago's Riot Fest. 

Bobbi Dunn Cantrell and her son Argyle traveled from Indiana to Douglass Park for the music festival. The birthday boy, now 16, held a sign that caught everyone's attention: "Hi! It's my 16th birthday! I'm autistic and Green Day is my special interest. Can I come on stage and sing 'Know Your Enemy?'", NME reports.

The mother and child had separated while she was on a quick bathroom break. "I was in panic mode all day because we got separated when I went to the bathroom and couldn't get back to him. He parked by the stage around noon and didn't leave all day," wrote Cantrell on Armstrong's Instagram.

Armstrong stopped "Know Your Enemy" mid-song due to health issues. "I have a really bad chest cold right now. I do. I'm a little bit sick right in here. So I need a volunteer. Who knows the lyrics to this song? Who knows it?" Armstrong asked the crowd.

The frontman's eyes landed on Argyle's sign, and up came the teen. Without missing a beat, he sang every word of the track from the band's 2009 release 21st Century Breakdown. His mom's heart leaped when she spotted him in the spotlight. "As soon as I saw him on stage I screamed 'OMG THAT'S MY KID!' What an amazing night! I am a new fan forever," she wrote.

Later, Argyle shared images of his big moment online, showing off his handmade sign and clips of his stage debut. "I'm so insanely grateful," he posted on social media.

Fans can catch Green Day next at Ocean City's Oceans Calling Festival on September 26. The band will then head west to Dana Point for Eddie Vedder's Ohana Festival on September 28. Fans can get tickets on the band's official website.