Warning: This article contains SPOILERS for Avengers: Endgame.

Avengers: Endgame ended on a solemn note with Tony Stark's funeral, and people have been wondering who the seemingly random kid/teenager was standing in the back. Starting with Jon Favreau's Iron Man and ending with Anthony and Joe Russo's Avengers: Endgame, Robert Downey Jr. has had quite the journey playing the Marvel superhero Iron Man on the big screen for the past 11 years - and since he's not returning to the MCU after this film, it appeared that his story could only end one way: in death.

In order to bring the story full circle, Iron Man managed to snag the Infinity Stones away from Thanos and use them to wipe out the Mad Titan and his time-traveling army of Outriders, Black Order, and more. But using the power of all six Infinity Stones was too much for Tony Stark to handle, and so, he died shortly thereafter. Giving audiences the chance to grieve Iron Man's death, Avengers: Endgame's final minutes contained a touching funeral for Tony. And characters from all corners of the MCU showed up for it.

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Everyone from Happy Hogan and Nick Fury (who inducted Iron Man into the Avengers) to Aunt May and Spider-Man, the Avengers: Endgame funeral scene featured one of the biggest ensembles in the MCU's history, and that included a surprising returning character: Harley Keener. For those who may not remember, Harley Keener was the kid Tony Stark befriends in Shane Black's Iron Man 3. Ty Simpkins reprised his role as Harley in the Avengers: Endgame funeral scene, but audiences may not easily recognize him since he's grown quite a bit since Iron Man 3 released in 2013.

Harley Keener in Iron Man 3

Simpkins' role in Avengers: Endgame was previously rumored due to his name appearing in the cast sheet for the movie on IMDb. But since IMDb listings for movies that haven't released yet aren't always accurate, the rumor wasn't taken too seriously. Obviously, Simpkins did return in Avengers: Endgame, but now that Tony Stark is gone, it's unlikely that he'll return once again. It's, unfortunately, the same for many characters who came back in this year's team-up movie.

Since Avengers: Endgame marks the end of the Infinity Saga, and sees several core MCU characters retire from the big screen, many characters who previously died on-screen returned thanks to the time travel plot, including Alexander Pierce, Howard Stark, Loki, and several more. But the one character that people were perhaps most confused about is Ty Simpkins' Harley Keener.

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