Why use different actors for Marty in each of the Shiloh movies?

Comment: Our class watched the movies of the first three Shiloh books. We think that the boy who played Marty in the first movie was the best one of the three. Why didn’t they use him for all the movies?

Phyllis replied: They would have, if they could have kept him from growing. Because there were several years between each of the Shiloh movies, the child actors had grown older and taller by the time the next movie was made. It wouldn’t have affected the adult actors much at all, and for the most part, the producers kept the same adult actors for all of the first three films. But you would have seen a considerable difference among the kids.