How old was Robert Downey Jr. in Firstborn?

It's common to wonder how old a celebrity was when they starred in a particular film. That kind of trivia can make the viewing experience even richer. Let’s take a closer look at that intriguing number.

At the moment the movie Firstborn was being made, Robert Downey Jr. was:

18 years old

After checking the dates, that’s the calculated age of the celebrity.

Our method involved using the first calendar day of the release year of Firstborn:

January 1, 1984

And the birth day of Robert Downey Jr., that is:

April 04, 1965

Movies tend to be released within a year of filming, so Robert Downey Jr. may have been one year off from the listed age in certain scenes.