I remember being 3 or 4 and realizing that my mon was at the same level of maturity as me. She was shouting at and insulting me as if she was my age (like kids fights on playgrounds), and I realized in that exact moment that she wasn't going to act like an adult with me.
She used to mother my brother while I awkwardly stood by and watched... which now that I think about it, is really cruel to do to a young child.
I'm lucky I have such old memories because I would not believe it otherwise. Narcs show their true face to kids who can't do anything about it. My Nmon probably even thinks that I forgot a lot of these details.
I didn't have words for mental illness or narcissim as a child. But I always knew that this behavior was off about her.