Over the summer, Mary went viral with a karaoke version of the hip-hop track, and when Missy spotted the footage, she posted the video to social media, calling Mary her "funky white sister".
Finally acquainted, Missy and Mary shared a warm embrace after the performance before Ellen got in on the action for a group hug.
"It was a shock, I never expected this", said Halsey about going viral and getting a response from Missy for the original video. Of course, DeGeneres had to ask Halsey to sing it for her audience. When Halsey was invited to perform on Ellen, she may have had a hunch that Missy Elliot would join her on stage but from her reaction, she still looked pretty shook. "Everybody wants to hear it".More news: Naomi Osaka Set To Land Adidas' Biggest Female Payday 09/14/2018
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Elliott then presented Halsey with a jacket that read "Missy's Funky White Sister" on the back. "Mary is one of the sweetest souls I met".
Mary's face dropped but she managed to pull herself together to finish the song with her idol. When I listen and she know all the words but the sound effects, she made the elephant noise and all of that...
Declaring herself "Missy's funky white sister", Halsey rapped a flawless rendition of the song during a karaoke barbecue.
'First I want to thank Ellen for just being incredible she will always be blessed because of her HUGE Heart!,' she captioned a video of her and Halsey.