Even if he started drinking at 13, it seems unlikely that cirrosis would develop far enough to kill him by 22. That’s pretty fast. The quantities of alcohol would have to be completely off the chart. Even then, I wonder if there was something else going on.
And you have NO friggin idea of what you are talking about. Take a look someday at the numbers of young alcoholics who end up being treated for pancreatitis and liver disease. It happens all too often
My father spent some time in Korea in 1970 and 1971; he told of meeting an Army helicopter pilot who was shot down (in VN) the first time on his eighteenth birthday (that sounds a bit young; it may have been his nineteenth birthday) and four or five times later on.
When asked what he was drinking, he would answer "Six rum-and-cokes", the asker would buy six rum-and-cokes, and he would down them faster than I could drink six glasses of water.
Word got back to the US a little later on that he was grounded for cirrhosis of the liver by the time he was 21.