Billie Eilish made a surprise appearance on stage with Green Day on Thursday to kick off one of two star-studded concerts in Los Angeles put together to raise funds for people affected by deadly wildfires in California this month.

"From the bottom of our hearts, we love you Los Angeles," Billie Joe Armstrong told the crowd, "and we've got your back no matter what"

One of the great challenges faced by the events during Grammy Week, including the FireAid benefit, is how to set the proper tone: How do you have a celebratory event like big concert or awards show without seeming tone-deaf to the tragedy and loss so many suffered in the Los Angeles wildfires that ravaged the