ARWEN OF THE ELVES
There are many races in the Lord of the Rings. Among these races is the Elves. One famous Elf is Arwen Evenstar.

Arwen is a daughter of Elrond, one of the most famous of elves, and Celebrían. Celebrían is the daughter of Galadriel, Lady of the Wood. This makes her Arwen's grandmother, because her mother, Celebrían, was Galadriel's daughter.

Arwen is only half elven. The reason for this is because she gave up her immortality to wed Aragorn Elessar. The movie has a scene in which this happens. Arwen and Aragorn are talking, and she gives him her necklace. This necklace apparently signifies her immortality. There are few details, but I believe that something was done to the necklace, making her mortal.