“Movie brat” is a term that refers to a film director that has gone to film school.
In the early 70’s, a new generation of movie directors came to power. These directors were different than the previous generations, because they learned about film through attending film school for years, and studying classic films.
These directors were the first generation to have film schools widely available to them.
Just about every (living) director whom you are familiar with is probably a movie brat, but Steven Spielberg, Francis Ford Coppola, Martin Scorsese, Brian De Palma and George Lucas are the names most commonly associated with the phrase ‘movie brat’.