Christina Aguilera and Adam Levine love to prank their fellow 'The Voice' coaches.
The 'Your Body' singer recently announced she will take a break from the show next season in order to focus on her new album and Christina admitted leaving will be ''bittersweet'' because she has so much fun with her fellow mentors.
She told E! News: ''It's bittersweet. I so enjoy being a coach to my team on 'The Voice' [and] and at this point in season three, all of us coaches have truly bonded.
''When me and Adam are on breaks backstage, you know, we're writing profanity with my red lipstick all over Blake [Shelton]'s trailer while he's napping inside. It's like we have definitely become like brother and sister. We goof around and play around. I'm going to miss it.''
While Christina has already spoken to producer Mark Burnett about returning after a break of one season, she thinks taking time out for her career will make her a better coach.
She explained: ''In order to be the best coach I can be on that show is to go out and be able to have the experience as an artist...create new experiences for myself so that I can then come back to the show and share that much more.
''Mark understands that we're artists first. In order to remain great coaches and to stay relevant, we have to go out and we have to still tour, see our fans one-on-one. I have to feel creatively fulfilled in order for me to then do my job as a coach and be on that show.''