Ariana Grande's brother Frankie recently uploaded a video of him and his sister singing karaoke in Japan, and you'll never guess what song Ariana decided to perform. No, it wasn't her hit song "The Way" or her duet with Nathan Sykes, but rather, "Baby" by Justin Bieber! We wonder if her tour buddy has had a chance to check out the clip.
Ariana isn't the only star who loves karaoke. In fact, some of our faves like Selena Gomez and One Direction have been caught in the act. Click through to see 10 stars doing karaoke, then let us know in the comments below whose song you love the most.
Ariana Grande sings "Baby" by Justin Bieber.