It’s so hard to watch your kids grow up, even when your kids are muscle-bound fictional characters. As “Avengers: Endgame” hits theaters this week, let’s think of the film ― a capstone for more than 10 years of Marvel movies ― as one big-budget graduation video. We know some characters will die, and some actors who have been kicking around the franchise for years will call it a day and hang up their spandex.

In honor of our old friends, let’s take a look at where the characters from “Marvel’s The Avengers,” which united the cinematic universe’s big heroes for the first time in 2012, were when we met them and where they are now.

Iron Man (aka Tony Stark)

Played by Robert Downey Jr.

First appeared: “Iron Man” (2008)

Then: When we first meet Stark, he’s a cocky, billionaire playboy and super-genius who manufactures war toys. After being taken hostage by a terrorist group and suffering a life-threatening injury, he invents technology with his fellow captive that both keeps Stark alive and allows him to fight all manner of baddies. Basically Ebenezer Scrooge at the end of “A Christmas Carol,” but with industrial espionage and electromagnets instead of banking and ghosts.

Every time you thank the stars that we’ve seen such sights on the big screen as the kingdom of Wakanda, a machine gun-wielding space racoon and Jeff Goldblum as space Jeff Goldblum, think kindly of Downey. The wildfire success of the Marvel Cinematic Universe was once just a spark of goateed charisma in a McDonald’s-colored tin can, rocketing into the sky to the tune of AC/DC.

Now: Still a cocky, billionaire playboy, but one who’s also the courageous heart of the extended “Avengers” family of super-folks. When we left him in “Avengers: Infinity War,” he had just watched in horror as his protege, Spider-Man (Tom Holland), and the Guardians of the Galaxy disintegrated into nothingness, courtesy of omnipotent villain Thanos (Josh Brolin). Currently stranded in space with cyborg warrior Nebula (Karen Gillan) and probably trying to figure out a plan to save those beyond saving.

The Hulk (aka Bruce Banner)

Played by Edward Norton/Mark Ruffalo (we can explain)

First appeared: “The Incredible Hulk” (2008)

Then: The 2008 “Incredible Hulk” finds skittish loner Bruce Banner (Norton), already prone to bouts of greenness, hiding out in Brazil from the U.S. military, who want to use the Hulk as a weapon. As Hulks are wont to do, he causes some destruction en route to saving the world’s bacon and ends up on the run.

Now: It’s been hard out here for a Hulk. Banner (recast as Ruffalo in the first “Avengers” flick, bringing scruffy nervousness to the field) did kinda end up as a government-adjacent weapon, since he became a member of the S.H.E.I.L.D.-aligned Avengers. However, he can’t really call himself a loner anymore. He had a weird romance with Black Widow, became science friends with Iron Man and did a stint as an intergalactic gladiator with Thor. When we last saw him in “Infinity War,” he had lost his ability to Hulk out, fighting Thanos’ forces in a jumbo version of the Iron Man suit before watching many of his allies disintegrate.

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Thor

Played by Chris Hemsworth

First appeared: “Thor” (2011)

Then: A brash thunder god from the interdimensional realm of Asgard, Thor was less a hero and more of a frat boy with a bad dye job. Sent by dad Odin (Anthony Hopkins) to the mortals’ world for a hero’s journey full of humble pie, he proves his mettle in defeating the schemes of his trickster brother, Loki (Tom Hiddleston). Dude learns to love, decides Earth beer ain’t half bad and earns the right to wield his cool magic hammer, Mjolnir.

Now: You thought Hulk had been through it? By the gods, Thor’s seen the business end of more than one plot twist. He lost an eye, his homeworld and his hammer in “Thor: Ragnarok.” In “Infinity War,” he got a new eye and a new hammer ― two outta three, not bad ― and returned to Earth in a bolt of lightning. Many bolts, in fact. A righteously angry Thor seemed to turn the tide against the forces of Thanos at first, but he watched helplessly as the bad guy won.

Captain America (aka Steve Rogers)

Played by Chris Evans

First appeared: “Captain America: The First Avenger” (2011)

Then: Plucky lil’ Steve Rogers really wanted to fight Nazis during World War II, but he was too small. Thanks to a top-secret super soldier experiment, he got big! A paragon of patriotic honor and human decency, he got to fight those Nazis, gosh dang it. But then he said farewell to his badass secret agent love, Peggy Carter, and took an ice nap for a few decades.

Now: For one thing: beard. Hi, beard. For another: Cap is still honorable and decent, but my dude seems a little tired. He had to fight for the soul of his brainwashed buddy, Bucky Barnes, aka the murder machine Winter Soldier. Then after the events of “Captain America: Civil War,” Steve spent some time on the run after a big blow-up with Iron Man. We last see him in “Infinity War” back on the grid, a more scuffed-up and jaded captain. He led the charge against Thanos in Wakanda — even going toe to larger toe with the big purple dude, much to the Mad Titan’s surprise. But then, most of his pals turned into powdered sugar. Bucky! No!

Black Widow (aka Natasha Romanoff)

Played by Scarlett Johansson

First appeared: “Iron Man 2” (2010)

Then: Black Widow’s debut in “Iron Man 2” was one of the first times we saw more than one Marvel Comics hero in action with another in this modern movie universe. When we meet her, she’s a S.H.I.E.L.D. agent undercover as Tony Stark’s assistant, with a truly heinous red wig (or at least I’ve always hoped it was a wig). She’s hyper-competent, and knows how to kick a few bad guys across a hallway like it’s a ballet. Mysterious. Leather-clad. Not a fully developed character — Johansson herself has called Black Widow a “sexy secretary” in her first appearance.

Now: Nat’s become one of the power players of the MCU, albeit a still-mysterious one. We really haven’t learned a whole lot more about her — some references to her shady Russian past, “red” in her ledger and sterilization — but not a whole lot of concrete biographical detail. By the time “Infinity War” rolled around, she had formed an even tighter alliance with Captain America. (Also, she went blonde.)

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Hawkeye (aka Clint Barton)

Played by Jeremy Renner

First appeared: “Thor” (2011)

Then: Listen, of all the Avengers, Hawkeye’s gotten kind of a short stick in the translation from the pages of Marvel. In his original comics incarnation, he’s a rogue, a carnival archer and thief who joins the side of the angels and busts chops at any given opportunity. He’s a shadowy black-ops marksman when we meet him in “Thor,” and he’s Black Widow’s secretly brainwashed co-worker in the first “Avengers,” an everyman cipher who shoots arrows real good.

Now: Marvel’s filmmakers gave our guy a family and a farm, which was nice of them. He decided to hang up the bow, then took the bow back down to support Cap in “Civil War,” then made a deal to hang up the bow once more under house arrest when it all went south. We didn’t see him in “Infinity War,” but he’s looking like a dark-and-broody loner type in the “Endgame” trailer. Would be a shame if that nice family got dusted, no?

Nick Fury

Played by Samuel L. Jackson

First appeared: “Iron Man” (2008)

Then: Our international man of espionage, our favorite eyepatched head-hunter for S.H.I.E.L.D., our glue. If Tony Stark was the flame that lit the candle of the Marvel Cinematic Universe, Fury was the Bic lighter. He first shows up as an effortlessly cool spymaster in the post-credits scene of “Iron Man” to tell Stark that he’s putting a team together. We all know how that turned out. If you want to be technical, the first time we see Fury chronologically is in 2019’s “Captain Marvel,” with two good eyes and a full head of hair, a lower-level S.H.I.E.L.D. operative teaming up with amnesiac Kree-powered pilot Carol Danvers (Brie Larson) to ferret out Skrull operatives on Earth.

Now: Dust. Powder. Soot. Ashes. Cinders. Particulate matter. The consistency of a jar of McCormick ground cinnamon. Allergens in the wind. But before that, paging Captain Marvel to come help out.

Loki

Played by Tom Hiddleston

First appeared: “Thor” (2011)

Then: We were just going to cover the heroes, but Loki is such a memorable part of the Marvel movie family, we couldn't resist. Thor's adopted brother schemes to take the throne of Asgard in his first outing. He gets Thor banished to Earth and briefly succeeds before getting his Frost Giant behind handed to him and promptly escaping into the clutches of Thanos. (Well, we didn't know that at the time.)

Now: Loki was a delicious villain in the first "Avengers," but over the course of the next seven years of movies, he became more complex, at time aiding his brother. (And then usually backstabbing him, but still.) In "Infinity War," sadly, Thanos snapped Loki's neck. Not that the god of mischief has ever let a little thing like death stop him.