"He came and saw the show and overall is a pretty hilarious guy," Jonas, 19, tells MTV of Stamos, who played the role of J. Pierrepont Finch in 1995. According to the "Who I Am" singer, his bromance with the "Full House" alumnus, 48, is "like dynamite."
"We watch a lot of YouTube videos. We talk about music quite a bit. He's a big music fan," Jonas explains. "He's a really good dude."
Jonas and Stamos both performed in "Hairspray" at the Hollywood Bowl in 2011 and have remained close ever since.
Having someone to confide in has been a huge help for Jonas, who joined the cast after "Glee" star Darren Criss ended his limited three-week engagement.
"John's been really kind through the whole process, because he played the role. He knows what it takes to do it," Jonas tells MTV. "It's a cool older-brother-type vibe in that sense. He's everybody's Uncle Jesse."
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