Captain James T. Kirk’s father — the late George Kirk — will probably feature in the next big-budget Star Trek cinematic adventure, but time travel might not actually bring the two together. And if Chris Hemsworth is not reprising his role as James Kirk’s father via time travel or flashback, it’s possible that Hemsworth could be playing Jim Kirk’s brother.

When MTV asked actor Chris Hemsworth if the elder Kirk will meet his son (Chris Pine) via time travel or an alternate dimension he said, “I honestly don’t know.” As reported widely, Hemsworth has been enthusiastic about the concept for Star Trek 4 saying what J.J. Abrams pitched him for the story was “amazing.”

Obviously, the details of what this means probably won’t come to light until at least the first interview with screenwriters Simon Pegg and Doug Jung or a trailer. But if time travel isn’t involved, that news may help assuage fears that the Kelvin Timeline Star Trek films could create yet another divergent dimension, this time where George Kirk lives, again.

Still, the July press release from Skydance and Paramount Pictures seemed to confirm Hemsworth was returning as Kirk’s father, reading: “In the next installment of the epic space adventure, Chris Pine’s Captain Kirk will cross paths with a man he never had a chance to meet, but whose legacy has haunted him since the day he was born: his father.”

LEFT: William Shatner as Captain James T. Kirk. RIGHT: William Shatner as George "Sam" Kirk

In the original Star Trek, George Kirk Sr. was not featured in any episode or film, though James T. Kirk’s brother George Samuel Kirk Jr. was very briefly glimpsed (as a corpse) in the episode “Operation-Annihilate!” famously played by a mustachioed William Shatner. Captain Kirk referred to his brother by his middle name “Sam,” in this timeline, while their mutual father was only established in media outside of the shows or films. Vonda McIntyre’s novel Enterprise is the first time James Kirk’s father was established as being named “George,” while the 2009 film was the first time it was established canonically.

Spencer Daniels played "Johnny" in 'Star Trek' in 2009

So, George “Sam” Kirk is James Kirk’s older brother. While there were plans to include George Kirk Jr. in the 2009 J.J. Abrams Star Trek, those scenes were changed to avoid confusion. (The character became “Johnny” in the finally cut.) Presumably, James T. Kirk of the Kelvin Timeline still has an older brother named George Samuel Kirk Jr. just like his Prime Universe counterpart did. Because if he doesn’t have a brother, then that means the Kelvin timeline actually diverges before Nero shows up from the future of the Prime Universe. And, if George Jr. does exist in the Kelvin Universe, it begs the question as to why he wasn’t on the USS Kelvin with his father and pregnant mother Winona Kirk when it was destroyed in 2233.

Could Star Trek 4 retcon all of this? Because if George Kirk Sr. is not traveling through time in Star Trek 4 to meet his son James, then perhaps Chris Hemsworth is playing his other son, George “Sam” Kirk Jr. Of course, the easy explanation without time travel and secret brothers means Chris Hemsworth is appearing in flashbacks only, prior to George Sr.’s death.

The next Star Trek film’s release date has not yet been announced.