I had a stroke a few years ago. They can happen very suddenly (mine was an acute ischemic stroke— where a clot breaks off from another part of the body and makes its way to the brain), but that kind of stroke is extremely rare in younger people and requires a pre-existing condition that could originate the blood clot, then a channel through which the clot gets to the brain (like a congenital heart defect.) I find the stroke story extremely unlikely because he would have had a well-documented chronic medical condition, and he’s young enough that he would been given brain surgery.