they can be different for everyone but from what I've heard the general consensus is that they're repressed thoughts or memories trying to surface. I've heard some claims that nightmares specifically can become more intense after something traumatic happens that you didn't get to deal with completely. I'm not sure about just regular dreams.
[ mostly because ellie herself doesn't have regular dreams. she just has nightmares. ]
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[ mostly because ellie herself doesn't have regular dreams. she just has nightmares. ]