John Gallagher Jr. was 13 in Rounders when he played the character 'Bartender'.
That was over 26 years ago in 1998.
This was his first recorded movie acting credit (although may not technically be his first actual acting role).
Today he is 39, and has starred in 26 movies in total, 24 of those since Rounders was released.
In Rounders, I think John Gallagher Jr. looks: