Also consider that it is almost impossible for "child rappers" (that catered to the Nickelodeon/Kidz Bop markets) to transition to the "adult rapper" audience. (See Kris Kross, Bow Wow, Lil Mama, Nick Cannon, Lil Romeo, etc.) Most times, they are treated as a 'novelty'...
There is a built-in dynamic that Rap music is premised on the hustles and struggles of (adult) life-- something that most of these 'child stars' avoid since they gain fame and riches prior to puberty. The only exception in this instance is Lil Wayne.
I agree, a child rapper is hard to take seriously as an adult.
I was only 11 when "Young, Rich, & Dangerous" dropped and I had already written them off by then.
I have to put Illegal over Kris Kross, Jamal >>>>>