Niënor (S. ‘Mourning’, b. FA 474) was the third child of Húrin and his wife Morwen. Born after her father had been captured in the Nirnaeth Arnoediad and her brother Túrin sent to Doriath for safety, Niënor spent her childhood in Dor-lómin with her mother; when she reached the age of twenty, the two secretly made their way to Doriath, hoping to reunite with Túrin.
When Morwen went to Nargothrond seeking news of Túrin, Niënor left the safety of Doriath against her mother’s knowledge, and soon after stumbled upon the dragon Glaurung, who cast a spell of forgetfulness onto her. From that point on, the memory of her life prior to encountering him was taken from her, and she wandered aimlessly as Níniel (‘Tear-maiden’) until being rescued by some woodmen, who led her back to their sanctuary of Ephel Brandir. It was here that she was reunited with her brother Túrin – though neither one recognised the other.
Níniel and Túrin were soon wed, and she became pregnant by him. When Glaurung finally lifted his hypnosis from Níniel, she was so horrified that she jumped to hear death from Cabed-en-Aras (FA 501). Túrin slew the dragon, avenging some of the ill deeds that had been committed, and then slew himself as well.