Eldarion was the only recorded son of Arwen and Elessar.
Eldarion's birth was significant in that he represented the union of the lines of Elros (through Aragorn) and Elrond (through Arwen) separated for millennia.
Eldarion became the second King of the Reunited Kingdom after the death of his father Elessar in Fourth Age 120. He was also recorded to have several sisters.
A hundred-and-five years after the fall of the Dark Tower, he encountered a renewal of Morgoth-worship during his reign.
His name in Quenya means "Scion of the Eldar". In Letter 338, J.R.R. Tolkien spelled this name Eldaron, this is probably a typographic error.
Portrayal in adaptations
2003: Peter Jackson's The Return of the King:
- While Arwen is on her way to the Grey Havens to leave Middle-earth and Aragorn, she has a vision of her future son (not named until the credits), which persuades her to stay. The boy is played by Sadwyn Brophy.