Mouse, maybe look at your first memory ever (and any other ones around it). When we got to looking at mine, I found a whole lot of stuff that is partially conjecture but "feels" right. My T confirmed that it sounded right to her too. But it makes sense of the "picture" of one's first memories and grounds them.

I remembered being read Dr. Seuss' McElligot's Pool (always have known it is my favorite Seuss book) when I was 2, and I bought a copy and took it to therapy and we discussed it in light of my other, first memory, and it was very interesting. At some point I had converted the happy, friendly whale on the last page into a sea monster!