No Doubt guitarist Tom Dumont has revealed his Parkinson’s disease diagnosis, just weeks before the beloved alt rock group is set to take the stage at the Sphere in Las Vegas. In a video message posted to Instagram, Dumont shared how he’s been preparing for the Sphere residency, noting that he’s enjoyed “looking through old photographs and relearning old songs.” He went on to explain how the experience has made him think about “how grateful I am for the life I’ve gotten to lead as a musician all these years.” Dumont, who joined No Doubt in 1988 and has remained...