Hedren As the Lead
Marshall believed in his wife’s ability to lead the line; that’s why he cast her as the mother; the lead role in the movie. To further keep things close to the family, the pair decided to cast their own children as the Kenyan’s children in the movie. To be fair, they were all also actors.
Hedren was adamant at getting Jack Nicholson to play the role, but he wasn’t interested in being that close to a hungry set of predators; nor was any other actor. So, naturally, Marshall had to be cast as Hank, the Kenyan biologist.