The concept of memories blending together resonates after watching a recent Kurzgezadt video entitled "How Are Memories Stored Inside Your Brain?". It makes the point that the very act of recalling a memory changes it:
https://www.youtube.com/watch?v=PqtggjVAi8M
> But memories are not static like photos. Like dioramas made from wax, each time they’re under the spotlight of your attention they can melt and change a tiny bit.
Very poetic metaphor!
I suspect my oldest memory, of me getting into a booster car seat as a child, is no longer the actual memory, but the accumulated imaginings of me trying to remember that specific memory, masquerading as a memory.