Greg Stewart is the name of a character who makes a single appearance in the Season 3 episode Little Wolf (episode).
Greg Stewart is the heir of the enormous Stewart fortune, which includes a very large estate. As Hawke remarked to Dominic, "When your name is Stewart and you live in a place called Stewartville, that oughta tell you something." Greg was also a war buddy of Hawke. Hawke was his instructor and he credits Hawke for emphasising the importance of safety and teaching the hot dog out of him. He considers Hawke the best pilot in the world.
Some time before the events in the episode, Greg had married Rainy Jennings. They were apparently very happy together and had a baby. Yet by the time of the episode, they had divorced, although they still loved each other. The reason for the divorce was not given but it is suggested that Greg's mother Mrs Martha Stewart had something to do with it. At one point, Rainy asked her why she broke them up. The key tension in the episode was the struggle for the custody of the baby. Greg, in compliance with the wishes of his mother, tried to persuade Rainy to sign over custody of the baby, while Rainy refused.
Greg had invited Hawke and Dominic down to his estate. He wanted Hawke to test fly an F6 Corsair and give his advice on whether to buy it or not. In addition, Greg wanted to spend some time with his friends and yarn about old times. However this never happened. Shortly after Hawke and Dominic arrived, Greg had to return the Corsair to San Jose. He crashed on take off and died.