The heart-breaking end in Avengers: Infinity War just got a whole lot gut-wrenching after James Gunn revealed what teenager Groot told Rocket Raccoon before he disintegrated.

The final moments in Avengers: Infinity War saw Thanos achieving his goal of wiping out a majority of the universe's inhabitants. With all the Infinity Stones in his possession, the Mad Titan selfishly turned Earth into an abandoned planet. With a snap of his fingers, Thanos wiped away half of the Earth's population.

'I Am Groot'

Superheroes turned to ash and disappeared right before other superheroes' eyes. What remains of the Avengers can hardly be called a team, much worse for the Guardians of the Galaxy. Rocket Raccoon is the only one left. Star-Lord, Drax, and teenaged Groot are gone. Gamora is presumably dead after Thanos sacrificed her life for the soul stone. While Peter Parker aka Spider-Man's disappearance stirred the emotions of fans, nothing can be more heart-breaking than Groot's final moments with Rocket Raccoon.

Viewers never really learned during the movie what Groot's "I am Groot" line to Rocket meant before he disappeared, so a fan asked the Guardians of the Galaxy director about it. Gunn's revelation just gave the catastrophic ending of Avengers: Infinity War more emotional heft.

Father-Son Dynamic

Teenage Groot's viewing of Rocket Racoon as his father deviates from the characters' dynamic in the original Guardians of the Galaxy. In the 2014 film, Groot was more of Rocket's protector and his loyal and close friend.

It also changes the fact that Gunn previously revealed that then baby Groot, now teenage Groot, is not the Groot from the first movie. Instead, he is the son of the old Groot, who died after he sacrificed his life to save the guardians.

Regardless, it was apparent from a few scenes in Avengers: Infinity War that Rocket Raccoon treated teenage Groot differently than his old pal. He acted like his mentor around the angsty teen. One scene in the film was on board their ship and Rocket scolded Groot for some presumably bad language. He also reprimanded the tree for sassing Star-Lord (Chris Pratt).

It remains unknown whether those superheroes who disappeared will ever return, although Pratt hinted as much in a recent interview. He said Gunn has already finished writing the script for the third Guardians of the Galaxy movie and expressed his excitement to return. It is likely that Groot will also return given that Star-Lord also vanished in Avengers: Infinity War.