Question: are elijah and klaus brothers?
Answer: Niklaus Mikaelson: Niklaus (known to most as Klaus, and to his maternal half-siblings as Nik) was the fourth child born to Esther and a werewolf named Ansel, the step-son of Mikael, the maternal younger half-brother of Freya Mikaelson, Finn and Elijah, and the maternal older half-brother of Kol, Rebekah, and Henrik.