Johnny Galecki was 11 in Murder Ordained when he played the character 'Doug Rule'.
That was over 37 years ago in 1987.
This was his first recorded movie acting credit (although may not technically be his first actual acting role).
Today he is 49, and has starred in 30 movies in total, 29 of those since Murder Ordained was released.
In Murder Ordained, I think Johnny Galecki looks: