Elwing:

The daughter of Dior, who was the son of Beren and Lúthien, Elwing married Eärendil and bore him two sons: Elrond and Elros. She joined Eärendil in his desperate journey into the West. It was due to her having brought him the Silmarill that they finally, successfully made the journey. She now resides on the western coast of Aman, in a tower that the sea-birds flock to.