LONDON — By the time she was 17, the Dutch teenager had written a harrowing memoir recounting repeated sexual assaults and her subsequent experience with post-traumatic stress disorder, depression and anorexia.

Last year, when she was 16, she approached an end-of-life clinic in the Netherlands seeking euthanasia or assisted suicide, but was rejected because her parents had been unaware of her request and she needed their permission, according to a local newspaper profile published in December.

When her sister announced that the teenager, Noa Pothoven, had died at 17 early Sunday morning — without revealing where or how — the story ricocheted and metastasized around the globe. It spurred an outpouring of condolences on social media and set off debates about the nature of the Dutch law on euthanasia and the spread of misinformation.

In the initial absence of detailed information from medical officials or from Ms. Pothoven’s family, the internet was flooded with inaccurate reports that she had died via legal euthanasia, raising questions about how someone so young could be allowed to die voluntarily.