Urwen (FA 465 ? - FA 468 ?), better known by her nickname Lalaith ("Laughter") was a Edain child of the House of Hador or House of Marach, the second child of Húrin and Morwen Eledhwen and sister of Túrin during the First Age.
Urwen was later named Lalaith after the Nen Lalaith a stream that ran by Húrin's house in Dor-lómin, because she was a happy child and brought much joy to the hearts of the household of Húrin during her short life. Her hair was yellow like the lilies that grew in the grass and was compared to an Elven child by most people. Túrin loved his little sister but played with her seldom and liked better to guard her unseen as she ran and played with song, but she was killed by a plague which came to Hithlum from Angband when she was still an infant.
Túrin never got over her death and always looked for her likeness in women ever after, which is one possible reason for the tragedy which befell him when he took Níniel as a wife later.
Her birth name was a Sindarin word that meant 'Fire maiden' and her nickname was also Sindarin word that meant 'Laughter'.
- The Silmarillion: Of Túrin Turambar pg. 198
- Unfinished Tales: Narn i Chîn Húrin
- The Children of Húrin: The Childhood of Túrin pgs. 38-40
- Lalaith at Tolkien Gateway