My intuition is that there's evidence out there that shows he cheated more, but people grow up a lot from age 12 to 19. That time period is basically the entirety of adolescence! I don't think it's fair to pin the actions of their 12 year old self on a 19 year old.

> but people grow up a lot from age 12 to 19.

I did broadly equivalent stupid shit when I was 12, 16, 19... I don't think I mellowed out until I was 25-30. 19 is young, 19 year olds are generally still in their peak stupid teenager years. Crime stats back this up: https://pinkerton.com/our-insights/blog/age-crime-curve

Again, as so many others have already pointed out, he was caught cheating at age 12 and again at age 16.

It's a third of his life ago. Were you the same person at 19 as you were at 12?

The trust is broken and equating it to fractions of someones life is the wrong measure. What has he done since he cheated at 12? Oh, he cheated in random games at 16. Surefire way to rebuild trust...

He cheated at 16 by his own admission.

A third of a life at 19 is barely a life at all