You can have a stroke at any age. A friend's wife had a very bad one at about 30 and has never regained the full use of her arm and leg on one side and still can't talk properly over 25 years later.
Can be horrible events, I wish the lad the best of luck and a return to good health. I am grateful for my own long odds level of recovery.
My mother in her 70s had one and is now looked after like a baby! She's Now in a Care home! She was fine one day & then pop! Her life as she new it was done with!