picasso. >> it really is. >> reporter: having charles schulz's son and grandson as writers on the film made staying true to the characters easier. schultz's son was particularly influential for this scene. >> craig schultz is a pilot. and he owns a biplane that's a lot like the red barron's. he said, i want to show you what it's like to do dog fight maneuvers. everything up and he did stalls, loop the loops. it was really informative to me. >> reporter: being humble and open to new ideas is a trait the team here picked up in part from a familiar friend -- charlie brown. >> he represents what we all feel and never talk about. >> absolutely. >> we want to feel like we're all buttoned up and together. charlie brown lays it all out there. but we have to celebrate his attributes of kindness, honesty, and that never give up spirit that he's always had.