Dire Straits legend Jack Sonni, who was widely known as the band’s “other guitarist,” has died at the age of 68, the group announced Thursday. His cause of death is unknown, but he was reportedly suffering unspecified health issues earlier this week. On Tuesday, Dire Straits Legacy, a group of musicians with adjacent acts, had announced on social media that Sonni wouldn’t be participating in upcoming gigs “because of health problems.” Dire Straits disbanded in 1995, but Sonni had largely ended his music career years earlier after the birth of his daughters in 1988. During his stint with the band, around the time of their hugely successful album “Brothers in Arms,” he jested about his role as a guitarist behind Mark Knopfler, famously calling himself “the other guitar player,” a nickname that stuck. He was believed to be focusing on writing around the time of his death. In his final Facebook post on June 2, he said, “Well chilluns, the last social media post for the foreseeable future as I dive into getting my novel in shape for my agent’s publisher hunt. Play nice & be kind to one another! And hug them while you can.”