Robert Kennedy Jr.s voice is raspy due to a rare neurological disorder called spasmodic dysphonia. This disorder causes voice breaks during speaking and can make the voice sound tight, strained, or breathy. Kennedy has been public about being diagnosed with this condition since around 1996. Although there is no cure for spasmodic dysphonia, there are various treatments available, including speech therapy, botox injections, and surgery. Kennedy has stated that his vocal chords are very strong, but the neurological signals that are being sent are telling his vocal chords to spasm. Despite his condition, Kennedy has said that his voice is getting stronger.