U.S. Navy Petty Officer 3rd Class Johann Gokool lost his left foot when a bomb ripped a hole in the side of the USS Cole nearly a decade ago, but the injury was nothing compared with the mental torment that ravaged him almost daily.

He returned home to Florida suffering severe post-traumatic stress disorder and frequent panic attacks so violent he would launch into seizures and even fractured his own wrist several times as he flailed, sister Natala Gokool said Tuesday.

One of the brothers he lived with found him dead in their home last Wednesday, just a week after his 31st birthday, Natala Gokool said. His cause of death was unknown, though she said foul play was not suspected. The family believes the seizures just became too much for his body to handle.