Avril Lavigne ended up at Billie Eilish's 18th birthday party

Avril Lavigne caught up with E! News co-host Scott Tweedie for the latter's Instagram series, HappE! Hour. During this chat, the Head Above Water artist opened up about her friendship with 18-year-old chart topper Billie Eilish. Back in July 2019, the edgy pop veteran attended the Bad Guy artist's concert in Los Angeles. It was during this concert that the two artists had a chance to meet and talk. This meeting clearly meant the world to Billie, who later shared a snap from the encounter and wrote, "Thank you, for making me what I am." However, from what the Sk8er Boi rocker exclusively dished to Scott, it's clear that Avril is equally a fan of Billie's. "Her performance was amazing, she was super sweet and she said a lot of kind things about me in her interviews, that she listened to my music and stuff growing up, so it was really cool meeting her," the singer-songwriter relayed. And the night was certainly a memorable one for Avril. Not only did Billie's brother and music producer Finneas reveal that he too was an Avril fan, but she was also invited to the singer's 18th birthday party.