WARNING: The following contains spoilers for WandaVision Episode 6, "All-New Halloween Spooktacular!" now streaming on Disney+.Billy and Tommy are growing up fast in WandaVision, going from newborns to ten-year-olds in one episode. Now, they're exhibiting superpowers, with Billy taking after Wanda and Tommy taking after Pietro. Furthermore, they don't seem to be completely under Wanda's control, unlike the rest of Westview. The twins, as well as the other kids of Westview, continue to be a mystery; however, Avengers: Age of Ultron may have predicted that the children of WandaVision could be Wanda's downfall.
While visiting an abandoned, Sokovian building, Wanda and Pietro find Ultron. As they talk about why Wanda let Tony Stark take Loki's scepter, the Scarlet Witch reveals she knew Tony's fear would be self destructive. Ultron agrees, remarking how, "everyone creates the thing they dread." He brings up how those looking for peace create weapons, and villains create heroes. Ultron also mentions how kids will be the downfall of their parents, claiming, "children [are] designed to supplant them, to help them end."
This cynical train of thought seems more out there compared to the other conclusions Ultron makes. He is a robot designed to protect the Earth, so him making the correlation between heroes and villains, as well as peacekeepers and weapon manufacturers, is not out of nowhere. Even Vision sees a correlation between the rise of superheroes and supervillains in Captain America: Civil War. However, assuming all children will "supplant" their parents is extreme, but there may be some truth to this in WandaVision.
Throughout WandaVision, the kids of Westview are a mystery, with Billy and Tommy being the first children in the sitcom town to appear in Episode 3, "Now in Color." Even Vision notices how there are no kids in town besides their children during Episode 5, "On a Very Special Episode...;" however, the town has been very invested in kids.
Episode 1, "Filmed Before a Live Studio Audience," sees Mrs. Hart interrogate Wanda about why she hasn't had kids yet, and Episode 2, "Don't Touch That Dial," features a talent show dedicated to the children, despite there being no kids. The emphasis on kids without there being kids has left many viewers wondering what's going on with the children.
While Episode 6, "All-New Halloween Spooktacular!" has Pietro propose that Wanda kept all the children asleep because she wouldn't want to traumatize them too often, she doesn't confirm or deny this. Wanda could recognize that what she's doing is traumatic, so she is sparing the kids from what she's putting the adults through; however, she could be doing this out of fear as well, whether that is fear for their well beings or fear for herself. If Pietro is right, the children experiencing the trauma their parents are going through could be the wake up call Wanda needs to stop the Hex.
If it's not empathy for these kids, then her own children could be her undoing. During Episode 5, Wanda attempts to put the babies to sleep using her powers, but they do not settle down. She's been able to control the actions of others, so it's surprising her abilities can't phase newborns. Billy and Tommy later age themselves up, which appears to be out of Wanda's control as well. Furthermore, despite being born within the Hex, the twins question what Wanda says, like what day of the week it is, and they assume she can "fix dead," despite not being alive when their father, Vision, died.
Episode 6 goes even further to show that these kids could pose a threat to Wanda, especially Billy. Along with developing energy based powers similar to Wanda's, Billy is clairvoyant, being able to see beyond the Hex. He could learn about the truth of their reality thanks to this ability, and with powers like Wanda's, he possibly could undo the Hex, as well as her control over the residents. Their powers, cognition and free will could bring an end to Wanda's fantasy, and with Billy seemingly taking after his mother in regards to abilities, they could also "supplant" her, proving that Ultron was right.
Written by Jac Schaeffer and directed by Matt Shakman, WandaVision stars Elizabeth Olsen as Wanda Maximoff/Scarlet Witch, Paul Bettany as Vision, Randall Park as Agent Jimmy Woo, Kat Dennings as Darcy Lewis, Teyonah Parris as Monica Rambeau and Kathryn Hahn as Agnes. New episodes air Fridays on Disney+.