Letter shared on what would have been singer's 53rd birthday
Singers joined forces on Linkin Park's Projekt Revolution tour
The somber acoustic performance was filmed weeks before the late-Soundgarden singer's untimely death on May 18.
Chris Cornell, one of the most revered rock singers of his generation, has died at 52.
How one of the heaviest, smartest, and greatest rock bands of the Nineties staged an epic comeback