Re-watched Thor, noticed Frigga’s reaction to Odin calling Thor his firstborn
Played by: Rene Russo, Frigga is a fictional character appearing in American comic books published by Marvel Comics. The character appears in particular in those featuring the superhero Thor, who is Frigga’s stepson.
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There’s a next to zero chance this is actually foreshadowing Hela, but it is a good catch as she is probably frowning in reference to the fact that Loki isn’t their child at all, making Thor (as far as they knew when filming this movie) their *only* child, not firstborn.