Earlier today, Bob Weir shared some devastating news that his longtime friend and fellow musician Rob Wasserman was battling some serious health issues. Hours later and a tweet from the Grateful Dead guitarist confirms that his RatDog collaborator has passed on.

In addition to being a founding member of RatDog, as well as a partner in the Bob Weir & Rob Wasserman project, Wasserman has an incredible list of collaborators throughout his musical career, including Lou Reed, Jerry Garcia, David Grisman, Van Morrison, Aaron Neville, Brian Wilson, Neil Young, Jackson Browne and more. We are sorry to hear of his passing.

Enjoy this video, estimated to be from between 1989 and 1990, with Wasserman and Weir on Nightmusic:

Rest in Peace, Rob Wasserman!