NASCAR legend Kyle Busch died of severe pneumonia leading to sepsis, according to his family. “The medical evaluation provided to the Busch Family concluded that severe pneumonia progressed into sepsis, resulting in rapid and overwhelming associated complications,” the Busch family said. Two-time NASCAR Cup Series champion Kyle Busch passed away on Thursday. He was 41 years old. Earlier Thursday, the Busch family released a statement on Kyle Bushch’s deteriorating health: “Kyle has experienced a severe illness resulting in hospitalization. He is currently undergoing treatment and will not compete in any of his scheduled activities this weekend at Charlotte Motor Speedway....