She died, probably in her early teens.

Her bones fell or were placed in the cave, where the cool, stable conditions preserved the DNA in her cells against the chemical and biological processes that destroy ancient organic material almost everywhere else on Earth.

She was there for 90,000 years.

Scientists were there for a fraction of that time, working with methods that had not existed until the last few decades of the last century.

And when those methods met the bone, and the DNA spoke across nine millennia, the answer was so improbable that the researchers who read it had to verify it multiple times before they believed it.