I grew up in Honolulu, and every once in a while there would be a tsunami warning. I don’t know how old I was—I would guess 6 years old, give or take a couple of years—but during one tsunami warning my parents drove up a ridge and parked on the side of the road to wait it out. We had a VW Vanagon, and I remember sitting in the van playing with toys to pass the time. At some point, a girl around my age joined me in the van. Her parents had the same idea as mine, and I guess they invited her to play with me while we all waited.
I’m in my 40s now. I still think about that girl from time to time.
My first thought (you might even call it my gut reaction) was “my microbiome,” so it’s along similar lines to yours.