Final answer:
When Franklin was 21 years old, he suffered his first heart attack.
Step-by-step explanation:
When Franklin was 21 years old, he suffered his first **heart** attack.
Heart attacks occur when the blood supply to the heart is blocked, leading to damage or death of the heart muscle. They can be caused by various factors, including atherosclerosis (build-up of plaque in the arteries), high blood pressure, smoking, and a sedentary lifestyle.
It is important to note that the given information about Franklin does not have a direct connection to any specific historical event mentioned. The question seems to be asking about a personal health event in Franklin's life.