Maureen O'Hara is the tough one in this film
The conflict between Big Jake and his sons in this film is that they believe he abandonded them. He has been gone for fifteen years. They do not realize that their mother's strength and bull headedness is probably why he left and that she may have even kicked him out. Several clues in the dialogue suggest why he left. My opinion is that he was driven away by Maureen O'Hara because she was just as tough if not tougher than him and they simply could not live together. She, after all, turned the ranch into a multi-million dollar enterprise. Some insight into what makes her tick is revealed when Big Jake learns the ransom is a million dollars. He asks her "Do we" then he corrects himself, "Do you have a million dollars?" She responds that she has that and many times more. She was the tough business woman who turned the ranch into a profitable enterprise. Also, he tells the boys they don't understand who their mother really is. They and we don't really find out until the end of the movie. For example, in the beginning of the picture when he looks into the ransom box he asks her if this is the way she wants it. She says they are dealing with ruthless men and that they should give these men exactly what they asked for. We do not see inside the box at this point and just assume it is the million dollars. We find out later that it does not have any money in it at all. What she means by "exactly what they asked for" is that she wants him to kill them. She sent for Big Jake so he could hunt the kidnappers down and kill them. Not pay them the ransom. She doesn't even send the money just in case. She wants the boy back but vengeance on the kidnappers is her main concern. Her sons do not know this about her. She is the ruthless one and that is what her boys don't understand and the audience doesn't understand until the end. What do you think? The only bad part about this movie is that John Wayne and Maureen O'Hara do not have enough scenes together. They have some of the best chemistry in Hollywood history.
Great Movie.