There are a lot of characters in Avengers: Endgame. If you’ve made it this far into the Marvel Cinematic Universe, most of them should be pretty familiar to you, but there’s one face that shows up during one of the movie’s key moments that you might not recognize.

[Ed. note: This post contains major spoilers for Avengers: Endgame below.]

The latest Marvel movie all but bids farewell to three of the franchise’s biggest stars: Black Widow (Scarlett Johansson), Captain America (Chris Evans), and Iron Man (Robert Downey Jr.). Each gets a big send-off moment, but the one with the most fanfare is Iron Man’s.

In the end, Tony Stark dons the Infinity Gauntlet to save the day, but the exertion costs him his life. His funeral, which takes place at the lakeside home he shared with Pepper and their daughter in the five years after the events of Infinity War, is attended by practically every Marvel character you’ve ever seen. Maria Hill is there, Thaddeus Ross is there, Janet van Dyne is there, Nick Fury is there. The slow pan across the mourners allows ample time to ID all of them — except, perhaps, one.

There’s a tall teenager standing towards the back of the crowd who’s not entirely familiar, at least if you haven’t recently watched the Iron Man movies and/or have a knack for telling what people will look like when they grow up. The mystery kid is Harley Keener (Ty Simpkins), the boy Tony briefly took under his wing in Iron Man 3. He’s just grown a lot over the past six years.

It’s time to revisit Iron Man 3

In case you’ve forgotten, it was Harley who helped Tony when he got stranded in Tennessee, helping the superhero handle his post-Battle of New York PTSD and lending him some makeshift gear while the Iron Man armor was out of commission. By the end of the movie, he’s become something of a protege, with Tony gifting him with oodles of lab equipment as well as a personal upgrade to the potato gun he’d been wielding when they first met.

Though Tony spends most of Iron Man 3 trying to resist Harley’s attempts at ingratiating himself, the two are ultimately too similar for him to keep it up — they both have deep-seated issues relating to their fathers (Harley’s father abandoned his family) and are young geniuses when it comes to building things out of scraps. It’s a thread that pays off in Endgame when Harley shows up to Tony’s funeral, suggesting that the two have kept in contact since, and formed a bond that, along with Peter Parker and his actual daughter, defined him.