Although Billie Eilish and Finneas O’Connell began their musical careers intertwined as a brother-sister duo, both have been finding success in solo ventures as of late. Billie Eilish’s newest album has officially gone platinum (which, to be fair, Finneas helped write) and Finneas’s second solo album has been receiving quite a bit of positive attention as well. Despite their respective achievements, though, the siblings have remained close and collaborated often. Just this past week has provided one such instance.

Two days ago, Finneas made an appearance at the Newark, New Jersey, concert on Billie Eilish’s current North American tour. He came out while Eilish performed her early hit, “Happier Than Ever,” where he assisted the song’s conclusion with his unique guitar stylings. Eilish had her own guitar, leading to an incredibly fun duet where both artists were giving everything they had. As you can see in the enclosed video, the crowd was going nuts for it.

Later in the week, Finneas was given the honor to perform at the BBC Radio 1 Live Lounge all the way in London, England, as promotion for his newest album, For Cryin’ Out Loud!. He didn’t only play songs from the album, though, for he also showed his appreciation for the classic English rock group Radiohead by covering one of their hit songs “Fake Plastic Trees.” The album the song comes from, “The Bends,” came out two years before Finneas was even born, which shows how important it is for younger artists to honor those who came before them. His cover was posted exclusively on BBC Radio 1’s YouTube channel.

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