Rebecca Cusey responds to my post about the controversial “He’s adopted” line in The Avengers:
The line is not entirely throw away. It’s a reference to events in the Thor movie (one of the many running up to The Avengers that told the backstories of the characters.) Loki, the villain (played by Tom Hiddleston) was raised by the god Odin (Anthony Hopkins) and as a brother to Thor (Chris Hemsworth). Loki finds out he was taken into the divine household as a peace keeping effort on Odin’s part and is, in fact, not Odin’s son. He’s the son of Odin’s enemy, Laufey of the Frost Giants, whom Odin beat into submission and took Loki as his own. Loki does not take this well. Thus is born the rivalry between Thor, the biological son, and Loki, the adopted son. Being gods and all, it has consequences for everyone. Norse mythology, like superhero movies, explore issues of humanity on a grand scale.
This line hearkens back to the issues of adoption in an archtypical sense. Not that that will necessarily make anyone feel any better.
Read her take on the joke here and her review of the movie here.