I didn't think this was the case the first time I saw the film but the wiki states that she was the Bergen who killed his Grandma and rewatching the film recently I guess the brief glimpse we see in the flashback does kinda look like Chef.

but what I find confusing is that if this was cannon why wasn't it brought up in the film? like maybe the first time he sees her Branch could have had some sorta PTSD reaction and panics running away or becoming unresponsive for a minute which would work as a way to allude to his backstory earlier in the film before the flashback scene. reveals what happened.

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or they could have just had her confirm it herself like maybe when she has the Trolls captured she subtly alludes to it by maybe saying that Branch resembles a Troll she ate a long time ago or something like that.

like I said I just find it weird that if this is in fact cannon why it wasn't mentioned in the actual film itself? or either of the TV shows.

https://preview.redd.it/k5mn3dslp7sb1.png?width=842&format=png&auto=webp&s=99130001094b3bd44e5dbf176ed186b99c045899