When Katherine Langford was reportedly cast in Avengers: Endgame, it sparked a wave of speculation over who the rising 13 Reasons Why and Love, Simon star would be playing. To introduce a new character in a climactic movie like Endgame would have to mean she would be someone of huge importance, right? But much to the surprise (or confusion) of fans, Langford didn’t even appear in the fourth Avengers film. Directors Anthony and Joe Russo finally explained who she was playing and why her character didn’t make the final cut.

Spoilers for Avengers: Endgame below.

Avengers: Endgame was the end of an era for the Marvel Cinematic Universe, and the start of a new chapter for the titular Avengers. So it wasn’t crazy to assume when Langford was cast that she would be part of a new generation of superheroes — the most popular fan theories included everything from an older version of Cassie Lang, who in the comics becomes the hero Stature, to Kate Bishop, the fan-favorite heir to the Hawkeye title who will soon be making her own Marvel debut. But Langford was neither of these characters. She instead would have played a much more unassuming role in the greater MCU: Tony Stark’s daughter.

Anthony and Joe Russo revealed in an interview with MTV’s Happy Sad Confused podcast that Langford was cast as the teen version of Tony’s daughter, Morgan (played in the film by Lexi Rabe). But how can an older Morgan appear in Avengers: Endgame when at the end of the film she was 5 years old at most? Look to Avengers: Infinity War and Thanos’ visit to the “way station” after the Snap. Joe Russo said:

“There was an idea that we had that Tony was going to go into the metaphysical way station that Thanos goes in when he snapped his fingers. And that there was going to be a future version of his daughter in that way station.”

The way station was the mysterious realm that Thanos appeared in after he snapped his fingers and disappeared half the universe. There he met with the young version of his daughter Gamora who he had sacrificed to obtain the Soul Stone. Infinity War visual effects supervisor Kelly Port described the way station as “not a physical place, it’s not a memory, even… It just seems like an internal moment of reflection.”

But while that may have worked for Thanos, the Russo brothers discovered that it wouldn’t have the same effect with Tony after the hero snapped his fingers to dust Thanos’ army. Langford’s brief appearance as an older version of Tony’s daughter only ended up confusing audiences, Joe Russo explained.

“What we realized about it was we didn’t feel an emotional association with the adult version of his daughter,” Anthony Russo said. “So it wasn’t ringing to us and resonating with us on an emotional level.”

“The intention was that his future daughter, because these films are dealing with magic, his future daughter forgave him and sort of gave him peace to go. And the idea felt resonant,” Joe Russo added. “But it was just too many ideas in an overly complicated movie.”