CAMDEN -- Last week, Cole Galanti wrote a birthday card for his brother Ben Fox, who would have turned 18 on Aug. 31.

Cole "wrote that he missed him very much and hoped he would send him some signs" that they were being watched over, his mother, Nicole Galanti, told NJ Advance Media.

Ben, who attended West Deptford High School, was killed in June 2014 when he was riding his bike on Parkville Station Road and was hit by a car. The crash was a few months before his 15th birthday.

Each year since Ben died, his family has celebrated his birthday by writing messages to him and burning them, "to send the message up to heaven," Galanti said. It's a way for Galanti's family, especially her daughter, Julianna, and Cole, who was 6 when Ben died, to process the grief.

"We always ask for signs that we can't ignore," Galanti said. "Signs that are so evident that there's no other way it's not a sign from his brother."

And besides asking for signs, there has been plenty of listening to Green Day, a favorite band of the family and one Ben often listened to. On what would have been Ben's 18th birthday, the family had tickets far away from the stage for the band's show at the BB&T Pavilion in Camden.

But when the family arrived, a friend surprised them with tickets to get into "the pit," the area directly in front of the stage offering the best views of the band. Already, the evening was looking like a memorable one.

Then, Cole got to meet Amber Miller, one of his favorite personalities from Radio 104.5. But Galanti says the clearest sign from above was when Billie Joe Armstrong, the band's lead singer and guitarist, was looking for a fan to come up on stage and sing part of "Know Your Enemy," Cole's favorite song. The interaction was captured in a video available on YouTube.

"Do you know the lyrics?" Armstrong asks, pointing at Cole in the crowd. "Alright, get your f--ing a-- up here."

Cole, beaming, got onstage, hugged Armstrong and sang the chorus with him, before diving into the crowd and crowdsurfing.

"I was so excited for him," Galanti said, though she admitted she was frightened Cole would be sent to the back of the venue, which often happens to crowdsurfers. She didn't want to lose sight of him. But then, the crowd placed Cole down up front.

It was a special day for the family, who has since moved to Wenonah from West Deptford. Galanti wrote a letter on Facebook last weekend, thanking the band for bringing Cole onstage and bassist Mike Dirnt for giving Cole and his sister Julianna picks to take home as a souvenir.

"Not bad for a kid who has terrible stage fright," she wrote when sharing the Youtube video of Cole singing and stagediving.

So what's it like to have a son in the spotlight?

"It was really heartwarming for me," Galanti said. "Amazing things can happen even after a tragedy."

The band closed the show with Ben's favorite song, "Good Riddance (Time of Your Life)," which Ben had setup to start playing whenever he opened his laptop.

All through the show, as the family kept getting surprised with good things, Cole kept his brother in mind.

"He kept saying, 'thanks, Ben,'" Galanti said.

Joe Brandt can be reached at jbrandt@njadvancemedia.com. Follow him on Twitter @JBrandt_NJ. Find NJ.com on Facebook.