Arun was the father of Number Six and husband of Lyn. He was good friends with Number Four's parents, Lara and Liren.
Not much more is known about Arun other than the fact that he would have been raised by his grandparents, assigned a Cêpan who would have aided his Legacy training. He would eventually marry Lyn and they would conceive a baby girl who was chosen by Lorien to become one of nine in the next generation of Elders. Arun and Lyn left their child in the care of her grandparents while they honed their legacies further.
Arun later died fighting Mogadorian forces during the Invasion of Lorien.