Daily Mail
It's because of their talent and musical success that they are training the next generation of upcoming vocalists. And on Monday, Kelly Clarkson, Adam Levine, Blake Shelton and John Legend took the stage at the NBC Upfronts in New York, according to Just Jared. On Monday, Kelly Clarkson, 37, Adam Levine, 40, Blake Shelton, 42, and John Legend, 40, took …
