My parents are really old, and it's depressing. What should I do?

I'm 14. My mom is almost 64 and my dad is almost 66. Longevity runs in my mom's side, but all the men on my dad's side apparently never passed age 80 or something. Is my dad going to be dead by the time I'm in my late twenties? Sometimes he warns me that he could die early, and it's really saddening. What should I do? I'm sort of looking for uplifting advice here (I haven't received any so far).