Avengers: Endgame was the end of the arc of some of the original Avengers, including Captain America, who at the end of the film decided to go back in time to return the Infinity Stones and stay there to have the life he always wanted next to Peggy Carter. In order to undo Thanos’ snap and bring back the vanished heroes (and the rest of the population of the universe), Avengers: Endgame used time-travel, with its own complicated rules that only made Captain America’s decision more confusing than emotional.

After years as one of the biggest heroes in the world, and 70 years frozen underwater, Captain America was ready to retire, and when he saw the chance to go back in time and live a more relaxed life, he took it, and so he spent the rest of his life next to Peggy Carter. Cap’s decision has made fans wonder why he didn’t change some of the most horrifying events in history, among other questions that haven’t really been answered as everyone seems to have a different opinion. Another question (though less intense than the previous ones) is who knew about his time-traveling, and the answer can be tricky.

Related: Theory: Captain America Became Mr. Rogers After Traveling Back In Time

As seen in Avengers: Endgame, the heroes that went back in time came across with their past selves, with Captain America even fighting against himself, meaning that some of the time-traveling rules that other films and TV shows have taught don’t apply in Marvel’s universe. So, when Captain America went back in time and stayed there, the other Captain America was still alive, somewhere, being heroic and all. Captain America was everywhere at some point, so it’s impossible for those who knew Steve Rogers to not notice the similarities. That said, it’s obvious that Peggy Carter knew about his time-travel secret, and given that Steve was the father of her kids, they probably knew about it, too. Again, Captain America was a big hero, and they would have noticed their father was identical.

As previously mentioned, Captain America didn’t do anything to change history, opting for a more low-key life, so it’s unlikely that other characters knew about it. Nick Fury might have been aware, but only by chance. Peggy Carter was one of the founders of S.H.I.E.L.D, so it’s not totally crazy that Fury and time-travel Steve could have crossed paths at some point, with the latter explaining why there were two of him. Of course, characters like Falcon, Bucky, Hulk, and the rest of the heroes from his original timeline knew about it, but only decades later.

The time-traveling rules and consequences in Avengers: Endgame will continue to be a topic of discussion among fans until the writers and directors finally agree on their explanations, which won’t happen anytime soon (or perhaps ever). At the moment, there is no official, canon explanation for how the time-travel works, just off-the-cuff reasoning to answer difficult questions. But, for now, fans can carry on with their lives knowing that at least Peggy and their kids knew Captain America’s time-travel secret.

Next: Endgame's Time Travel Doesn't Make Sense Because Marvel Changed It