It began with just Bruno Mars on stage, who was then joined by Sting, who in turn was joined by Ziggy Marley, and then Damien Marley, in a rousing tribute to Bob Marley at the 2013 Grammys.
On display was how musical influences pass from one generation to the next. Marley, the eldest Marley that is, famously influenced Sting's own music (and his own sons, of course). Sting, in turn, influenced Bruno Mars.
The music is all different but shares some of the same roots.