The One About a Spare Cerebellum

This is … er … a lede:

Here’s a horrifying little story to kick off your weekend: A 16-year-old girl in Japan recently had a tumor surgically removed from her ovary — and when her doctors split it open, they found a tiny brain growing inside.

Or, you know, as the headline from Science of Us explained, “Doctors Found a Tiny Second Brain Growing Inside This Woman’s Tumor”.