Jonathan Brandis was 9 in Mystery Magical Special when he played the character 'Jonathan'.
That was over 38 years ago in 1986.
This was his first recorded movie acting credit (although may not technically be his first actual acting role).
In 2003 he died aged just 27, starring in 22 films in his career, 21 of those after Mystery Magical Special was first released. If he were alive today he would be 48.
In Mystery Magical Special, I think Jonathan Brandis looks: