The 51-year-old actor and 40-year-old actress praised their 14-year-old son at the movie's AFI Film Festival premiere Thursday. Jolie previously revealed to DuJour magazine Maddox worked as a production assistant on the project.
"We want to make it a family affair and have the kids running in and out of set," the dad-of-six told Entertainment Tonight on the red carpet. "It's fun to see your boy grow up and take on responsibility and [it's] very nice."
"Mad and I are now producing a film in Cambodia about his country and his history, so we love working together," Jolie said of First They Killed My Father. "It makes it so much nicer for me to not have to divide my time at home with my time at work."
"We home school, so now they're really determined to do all their work so they can finish early on a day and get out to set, so it's lovely," she added. "Now, we're sharing it, so it's very different."
Pitt and Jolie are also parents to 11-year-old Pax, 10-year-old Zahara, 9-year-old Shiloh and 7-year-old twins Vivienne and Knox. Three of the children are adopted, and the actress recently discussed the importance of her kids' cultural heritage with Vogue.
By the Sea marks Pitt and Jolie's first collaboration since the 2006 movie Mr. & Mrs. Smith, and opens in theaters Nov. 13. The film follows a married couple whose relationship breaks down while they are vacationing in France.