JOE是什么意思？

I first met Joe Ganz when we were both nine years old, which is probably the only reason he's one of my best friends.

If I had first met Joe as a freshman in high school we wouldn't even have had the chance to get to know each other

Why does the speaker say Joe Ganz became one of his best friends?

What has the speaker learned from his friendship with Joe

Joe is a day student, but I am a boarding student.