Aedan Mikaelson

Aedan Mikaelson is an Old One and the (chronologically) eldest sibling of Elijah, Finn, Niklaus, Rebekah, Kol and Henrik Mikaelson. He's the son of Mikael and Esther, who conspired to become Immortal and formed the Cult of Silas, he has been entombed for over a thousand years and conspirators are preparing his resurrection.

Trivia

 * Aedan is believed to be the name of the Mikaelson's eldest son.