A kid on my son's 13U team was 6'5, 320 pounds (and not a sloppy 320). He's now 6'6, 340 and is a starting offensive lineman for UGA but his body has basically changed very little since age 13. My wife took my son to his first session in the hitting cages and asked the big guy which one was his son...he replied "no ma'am, I'm on the team". He once got kicked out of a tournament because there was a collision at the plate where the opposing catcher blocked the plate (illegally) and when this kid ran into him, the catcher flew about 10 feet behind home plate. When the umps were challenged, he said that our big kid had done nothing wrong but he couldn't allow that type of violent collision without raising the ire of the other teams...in other words he was ejected for being big.
And yeah, he was one of several kids on the team with a full on beard.
Edit: it was a 14U team but my son and this big kid were 13 at the time.