updated 03/25/2010 AT 12:00 PM ET
•originally published 03/25/2010 AT 12:55 PM ET
“He has this thing where he tries to say everything that’s coming out of my mouth,” Lovato tells Radio Disney’s Ernie D, laughing. “But yeah, he doesn’t know what I’m about to say.”
Lovato and Jonas, who performed the duet “Make a Wave” on American Idol Wednesday, met on the set of Camp Rock in 2007, and Lovato toured with the Jonas Brothers the following year. The two quickly became best friends.