More details surrounding Brandon Blackstock's health battle before his death have come to light. A death certificate issued regarding Blackstock and obtained by People on Thursday, August 14, reveals that the music manager died after battling malignant melanoma at the age of 48. He died of natural causes, according to the Silver Bow County Coroner, but had also suffered seizures shortly before his passing. The outlet further reported that Blackstock's death certificate listed the seizures as "significant conditions contributing to death, but not resulting in the underlying cause.