[Editor's note: The following contains spoilers for WandaVision, Season 1, Episode 3, "Now in Color."]

In 2015’s Avengers: Age of Ultron, the MCU introduced fraternal twins Wanda (Elizabeth Olsen) and Pietro Maximoff (Aaron Taylor-Johnson). In the comics, these characters, also known as Scarlet Witch and Quicksilver, respectively, were mutants and the children of Magneto. However, in 2015, the X-Men and the word “mutant” belonged to 20th Century Fox, who had their own Pietro Maximoff with Evan Peters playing the role from X-Men: Days of Future Past onwards. The MCU’s solution was to instead say that Wanda and Pietro were “enhanced”, and had been given their powers by Loki’s scepter, which housed the Mind Stone. The MCU’s Pietro was killed in the Battle of Sokovia at the end of Age of Ultron, which seemed like a backroom deal between two studios who didn’t want to share speedsters.

In the years since Age of Ultron, Pietro has never even been mentioned. We’ve seen Wanda in Captain America: Civil War, Avengers: Infinity War, and Avengers: Endgame, but there was never any mention that she had a brother who died. While that obviously isn’t something that comes up easily in conversation, it was still a major part of her character and a grief that had never been reconciled. Instead, her arc was moved to her relationship with Vision, which also comes from the comics.

However, this week on the third episode of WandaVision, we finally had acknowledgement of Pietro’s existence and that he died at the hands of Ultron. It should be said that this acknowledgment is likely a byproduct of the fact that Disney now owns 20th Century Fox and therefore owns all Pietros (as well as the likelihood that the X-Men movies will almost certainly be rebooted, so Evan Peters’ version is over). And that’s good for Wanda as a character because losing a sibling would be a life-defining event for just about anyone. It’s clear that these two characters were close in Age of Ultron, and you can’t really get into the psychology and motivations of Wanda if you simply ignore the fact that her brother died.

If I can engage in some idle speculation, mentioning Pietro opens the door for a return of some kind. On the one hand, characters who die should probably remain dead to maintain a sense of stakes, but also Wanda is a character than can warp reality, and it would be fascinating if WandaVision was building up to bringing Pietro back in some form. It’s not that he was some unforgettable character (Taylor-Johnson was fine in the role but wasn’t given the showstopping moments Peters received in the X-Men movies), but rather that the MCU has a toy in the toybox they can use again without worrying about if it conflicts with another studio’s character rights.

I also think when you bring in another character who’s important to Wanda, it makes her a more interesting character. Up to the point, the only characters she’s really had a relationship with are Pietro, Hawkeye, and Vision. If you bring Pietro back into the fold, you open up new options rather than forcing Wanda to rely solely on Vision since Hawkeye is off doing his own thing.

Again, this is all speculation, and maybe Wanda was just expressing her thoughts about Pietro because he was her twin brother and she had just given birth to twins. But as Pietro quipped in Age of Ultron, “You did not see that coming?” we may want to be on the lookout for the return of Quicksilver.