Our own investigation in moments. Coming up later here in the broadcast. The brothers who take to the field and compete against one another. Tonight those parents already worried about the son who... See More
Our own investigation in moments. Coming up later here in the broadcast. The brothers who take to the field and compete against one another. Tonight those parents already worried about the son who will lose. "Good morning america's" josh elliott is in new orleans. Reporter: As brothers and rivals, jim and john harbaugh will work opposite sides of the field tonight while somewhere in the super bowl stands a mother and father quietly root for both teams. Jackie and jack harbaugh have spent a lifetime guiding their boys to this history making moment. Still just last week mom joked that she was hoping for a tie. Well, I think that the nfl changed that rule. I think if it ends in a tie, it will be a tie. Reporter: But they know only one team can win, and so only one of their sons can be the winning coach, and at the end of the night, brother will still face brother. I've given absolutely no consideration to the post game handshake or bear hug or anything else. Have not thought about that for one second, jerry. Have you, jim? I have not. Reporter: But mom and dad have thought about it quite a bit. We're going to hug both of them. My thoughts go to that one that will not experience the thrill of victory, and that's where our thoughts will be. Reporter: Josh elliott, abc news, new orleans.
This transcript has been automatically generated and may not be 100% accurate.