Does every fictionkin have to have memories that later happen the showseriesetc?

Not every fictionkin has memories/has to have memories at all.

I talk about memories a lot because they’re important to me, and my identity. They’re how I knew I was me, for a long time. I have many of my memories as Ken, stretching from long before the series, to long after. I even remember the day I died (something I don’t recommend if you can avoid it.)