With Spider-Man: Far From Home's post credits scene, one of the most important secrets in the MCU has been unleashed, with Mysterio revealing Spider-Man's identity as Peter Parker, the future has never been less certain. Which makes it the perfect time for Marvel to send Peter out on his own -- calling on his long lost sister to help him navigate the coming onslaught. And discovering the truth about his parents' past.

Since plenty of Spidey fans won't even know about Peter Parker's sister, Teresa Durand, the beauty of this opportunity requires some explanation. Teresa was introduced back in 2012, as the younger sister orphaned along with him, but separated from the family (for unknown reasons). What fans know for sure is that she is a CIA agent with the knowledge and skills to help protect Peter, once he's been outed as a target for every Marvel villain and hired gun. She also has the experience working alongside Marvel mainstay Nick Fury to force an introduction. But believe us, that's only the beginning of the story Sony and Marvel could begin to tell... and the movie universe has prepared fans more than even they realize.

Teresa Has The Secrets Spider-Man Wants

Spider-Man Family Business Sister Teresa

When the time came to reboot Spider-Man in the MCU, the decision was made to leave Uncle Ben out of the story entirely. It made sure Homecoming didn't re-tread a downer origin story, but as a result, not much is known about the Parker family of the MCU (aside from Aunt May, of course). Which only gives more incentive to have Teresa enter the picture as the sibling Peter never got to have, while also fleshing out the Parker mythos. And the most compelling reason is that when she made her debut in Spider-Man: Family Business -- an incredible title for the next Spider-Man movie -- she did it by saving Peter's life from threats more tailored to her training as a CIA Agent... just like her and Peter's parents. And if that comes as a shock, strap in.

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It turns out Peter's parents, Richard and Mary Parker, weren't 'just' CIA super spies. They were the kind of spies that seal Nazi gold in a tomb protected by a killer robot, secured so only Richard's biometrics could access it. Nobody knew about this, of course, and least of all their orphaned son. So when armed men came to kidnap Peter as Richard's closest living relative and most likely match, Peter was caught completely off guard. Thankfully for him, he was saved by a highly trained spy who informed him of the entire plot. Including the fact that she was the second closest match, as Peter's biological sister.

Spider-Man Needs His Sister's Protection

Spider-Man Sister Teresa Marvel Comic

Even more lucky for Peter, Teresa introduced herself as a highly trained CIA spy -- recruited and mentored by Nick Fury himself. Teresa told Peter they were both targets, and would have to work together to survive the trap their parents had inadvertently set for them. The villain after the Nazi gold is eventually revealed to be the Kingpin of Crime, Wilson Fisk, having tracked Spider-Man to the tomb in question. There he learned Peter Parker was under the mask. But even worse, Kingpin revealed his larger plan: using a mutant named Mentallo to trick Teresa into thinking she was Peter's sister, in order to lure him into the open. All of Teresa's memories of the Parker family were pulled from Peter's mind, but Peter being Peter, assured her he still considered her just as important. A gunfight later, and Teresa shifting to follow Peter's code of non-lethality, the showdown was over. A blast from the aforementioned psyched wiped Peter's identity from all minds present. Of course, Family Business made sure to conclude with Teresa's DNA called into question...

Teresa faded into comic lore until Peter Parker: The Spectacular Spider-Man #1, when she reappeared after regaining her knowledge that Peter Parker was Spider-Man. Their brother/sister bond picked back up, and when accompanying Spider-Man on a mission back in time, Teresa sought out Nick Fury in hopes of learning her true origin. She finally did, when she accessed a safe house belonging to Richard and Mary Parker, and discovered she was, in fact, their biological daughter. For real. Writer Chip Zdarsky explicitly confirmed Teresa is Spider-Man's sister, so there's no debate as far as we're concerned. And in the process, made it perfectly understandable why she would adopt a Falcon-like set of mechanical wings, and save Peter's life more times than we can count.

Sony's Stage is Set For Spider-Man & His Sister

Spider-Man Sister Teresa in Comic

While the fact or confusion surrounding Teresa and Peter's relations may be too confusing for the MCU, the end result is a brother and sister bond. Thanks to the larger events in the MCU, the next Spider-Man movie is actually perfectly set up to introduce Teresa as Peter's lost sister. Not only a few years older, but with the possibility she survived the Thanos snap, old enough to completely sell her status as an elite CIA Agent. If a plot relying on Nazi gold is too far-fetched, then the army of villains now coming for Peter Parker gives Teresa an even simpler reason to come to her brother's aid.

More than anything, this is a story that begins and ends with the Parker family, including a role for Aunt May to play (either withholding information to protect Peter, or learning the truth along with him). Having started this new Spider-Man story with Homecoming, before sending Peter Far From Home in the sequel, it seems like fate that in his hour of greatest need, it's the family he never knew he had which returns to protect him. And with Peter set to become the center of his own Spider-Man movie universe at Sony, the addition of Peter's sister -- directly adapting the comics -- seems too good an opportunity to pass up.

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