The direct descendant of Elros is Aragorn. In terms of genealogy, Elros would be Aragorn's great grandfather with about 60 "greats." This makes Elrond Aragorn's great, great, etc. uncle, and since Arwen is the Lord of Rivendell's daughter, she and Aragorn are first cousins many times removed.
Aragorn was a descendant of Elros Tar-Minyatur through the line of the Lords of Andúnië to Elendil, High King of Arnor and Gondor. Like all of the kings before him, he was related to Elrond through the House of Elros.
The Valar (the angels or lesser gods who shaped and governed Arda, the material realm) lifted the island up from the depths of the sea as a gift to Men for their fight in the war against Morgoth. Elros, the twin brother of Elrond, became the first king of Númenor, marking the beginning of Aragorn's kingly lineage.
In T.A. 2933, Elrond took Aragorn as his foster-son in Rivendell, and had Arwen live in Lothlórien with her grandmother. Elrond named Aragorn Estel ("Hope") and concealed his heritage from him until he came of age.
Aragorn was a descendant of Elros Tar-Minyatur. His ancestorArvedui was wedded to Fíriel, who bore their son Aranarth, making Aragorn the last descendant of Anárion as well. When Aragorn was only two years old, his father Arathorn was killed while pursuing orcs. Aragorn was afterwards fostered in Rivendell by Elrond.
After the war ended Elendil was dead. Therefore Isildur, his eldest son, was then the (last) rightful king of both Gondor and Arnor, and therefore his descendant Aragorn was also the rightful king of both kingdoms.
Heir of Isildur was the title of thirty-nine lords of the Dúnedain descended in right line from Isildur the son of Elendil, from his son Valandil to Aragorn Elessar, who reunited the Kingdoms of the Dúnedain in Middle-earth.
Aragorn is a fictional character and a protagonist in J. R. R. Tolkien's The Lord of the Rings. Aragorn was a Ranger of the North, first introduced with the name Strider and later revealed to be the heir of Isildur, an ancient King of Arnor and Gondor.
The Third Age. At the beginning of the Third Age, Elrond married Celebrían, daughter of Galadriel. They had three children: twin sons, Elladan and Elrohir, and a daughter, Arwen.
Through her great-grandmother, Idril, Arwen was a descendant of King Turgon of the Noldor. Through her mother, she was the granddaughter of the Elf-queen Galadriel of Lothlórien. Through both of her parents, Arwen was a direct descendant of the ancient Elven House of Finwë.
A legend says that the Wizard Gandalf had brought such a stone, called the Elessar, from Valinor. He gave the Elessar to the Elven Lady Galadriel and remarked prophetically that she would pass it to another, who will also be called Elessar. From this would come Aragorn's royal name Elessar (Quenya for "Elfstone").
The story was abandoned, but Tolkien reused the characters and events. Isildur features briefly in voiced-over flashback sequences of Peter Jackson's The Lord of the Rings film trilogy. The video game Middle-earth: Shadow of War departs from Tolkien's narrative by having Sauron make Isildur into a Nazgûl or ringwraith.
Arwen probably got to know Legolas as her husband's friend and as the leader of the Elven colony in Ithilien. As Mary Tower points out, it is possible that they are distantly related, but it's nowhere stated.
He did not want to see his daughter Arwen married to Aragorn, a mortal, and did his best to stop her from following her heart. Not only did he treat Aragorn– and the race of men in general– with contempt, but he went as far as lying to Arwen about what he saw of her future.
Though neither is someone you'd wish to annoy, Galadriel is generally considered more powerful than Elrond in Lord of the Rings. Not only is she older than her Rivendell counterpart, but Galadriel witnessed the light from Valinor's Two Trees, giving her a mystic quality.
Galadriel was one of the Ñoldor who came to Middle-earth wishing to see the lands and rule a realm of her own. She came with the second host of Elves from Aman with Fingolfin and Finrod. In Doriath, she and Celeborn fell in love and married.
Arwen was the youngest child of Elrond and Celebrían; her elder brothers were the twins Elladan and Elrohir. Through her father, she was the granddaughter of Eärendil the Mariner (the second of the Half-elves), great-granddaughter of Tuor of Gondolin, and therefore a direct descendant of the ancient House of Hador.
Arwen. Galadriel's granddaughter and the daughter of Celebrían and Elrond. After the War of the Ring, Arwen marries Aragorn II Elessar and becomes Queen of the Reunited Kingdom of Arnor and Gondor. Like other Half-Elves, Arwen has the birthright to choose either immortality among the Elves or mortality among Men.
Legolas does not marry or have any children, based on the appendix of The Lord of the Rings. Regardless of who his mother was, Legolas is the last of his line. When he sails into the West at the beginning of the Fourth Age, he leaves no family members behind.
Arvedui, Isildur's Heir through twenty-three generations, was the last King to rule in the north; he attempted to reclaim the High Kingship, but failed, and the last remnant of royal Arnor was overrun by its enemies. Now the line of Isildur in the north became forgotten by nearly all.
Aragorn's mother, Gilraen, was one of the Dúnedain - the line of Men descended from Aranath, the last king of Arnor. Her father was Dírhael, and he was good friends with Ardor, the Dúnedain Chieftain and Aragorn's grandfather.
Due to dissention among the sons of King Eärendur, the realm of Arnor was divided in three separate kingdoms. The eldest son, Amlaith, became the first King of Arthedain and his descendants maintained the line of Isildur while the line died out in the other two kingdoms.
This, of course, means that Elendil is also one of Aragorn's ancestors, which is one of the subtle ways that The Rings of Power is able to tie itself back to the Lord of the Rings story. Elendil's bloodline became the long-lived Dúnedain, of which Aragorn was a part.
She drowned in the same waters now calling out to her son, a son who will change Middle-earth forever. And that's why for all the pain her family has endured, losing her might have been a gift. Because, as Númenóreans rightly believe, “the sea is always right.”
