Cause, while I was rappin' they was growin' up fast
In verse one and two, the characters in the story were children. By the time the third verse comes around, they’re older, and they meet. So as he was rapping, they literally grew up fast — mentally & physically. In the later case, growing up “fast” meaning they are doing things way ahead of their time (ex. Sex, drugs, etc). While Lupe was trying to get his name to a point where people actually listened to him, nobody was there to step in to teach the youth right from wrong.
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