In the The 39 Clues series, Jonah Wizard is the Cahill's famous face - he's a star hip-hop musician, and he gets mobbed everywhere. He's a celebrity - he flies private planes, has tons of money, etc. He talks like a 'gangsta'. Here's an example:
"Wassup, Pierce Landing? The Wiz is in the house!"
-The 39 Clues; Unstoppable: Flashpoint, chapter 26
...
"Legit, I've got some things to tell you about my man, J-dog," Jonah harangued the crowd.
-The 39 Clues; Unstoppable: Flashpoint, chapter 27
Was Jonah based on any specific celebrity?
