A player theory suggests that Jason Duval, the protagonist of GTA 6 who has yet to make an official appearance, is the descendant of Arthur Morgan and Sadie Adler from Red Dead Redemption 2. However, this speculation lacks substantial evidence when considering character appearances, timelines, and the distinct worlds of the two games.
Supporters of this theory mainly compare close-up facial photos of the two characters, citing "identical eyes" as evidence of a blood relation. However, analyses point out that their eye shapes and colors are actually different. The limited visual similarity is more likely due to Rockstar's consistent style in eyelashes, skin shading, and facial animations developed over years of using the RAGE engine.
The timeline also fails to support such a relationship. The story of Red Dead Redemption 2 takes place in 1899, the same year Arthur dies from tuberculosis. Even if he had a child born around 1900, after more than a century, that child would only be an ancestor several generations removed from Jason.
Furthermore, Red Dead Redemption and Grand Theft Auto are considered separate universes, with scattered Easter eggs insufficient to prove any canonical connection. Arthur and Sadie's closeness stems from their shared grief over losing family members; the original game does not establish a romantic relationship between them. Arthur already has a past with Eliza and his son Isaac, while his primary romantic interest is Mary Linton.