I could believe even quite a bit younger, there are some wildly talented children and it's easy to believe Michaelangelo to have been one.
It is frustrating that the article is so coy about the evidence around the premise of the article! But, this website and the youtube video this article is based around both lean more towards pop than investigative.
Why? There were other talented people who produced masterful works at an early age. From the same time as this there's a Dürer self-portrait, also aged 12-13:
https://en.wikipedia.org/wiki/Self-Portrait_at_the_Age_of_13
> We don't have any really reliable records from that time.
Uh, no. There's no documented attribution of that painting to Michelangelo; that doesn't mean that other things weren't reliably recorded.
Source: know how to draw really well.
https://www.metmuseum.org/exhibitions/listings/2009/michelan...