Jason Ritter was 9 in The Dreamer of Oz when he played the character 'Harry Neal Baum'.
That was over 33 years ago in 1990.
This was his first recorded movie acting credit (although may not technically be his first actual acting role).
Today he is 44, and has starred in 55 movies in total, 54 of those since The Dreamer of Oz was released.
In The Dreamer of Oz, I think Jason Ritter looks: