Esther's history prior to becoming a mother is revealed on The Originals Season 2 Episode 6.
Oliver is scheduled to be executed at midnight for his part in helping the teen wolves escape activating their curses. Esther still has Elijah strapped in his dream state, weakening him in hopes he will decide to join her.
Klaus learns that Esther has Elijah and endeavors to rescue his brother, cutting Hayley out of the adventure. She turns to Marcel and Gia for help saving Oliver from his scheduled fate, but first she needs to find the werewolves' Alpha so that they will no longer be able to obey Finn.
Finn, as Vincent, tries to convince Cami to leave Klaus alone so that she can stay out of danger. When he places her drink order, she gets spooked and leaves the bar in a hurry. She consults one of the books Uncle Kieran left for her and, with Marcel's help, learns that Finn is hitching a ride inside Vincent. When Marcel suggests she stop seeing Vincent, she vows to use her new knowledge to their advantage.
She encounters Jackson in the woods and he refuses to help. His friend Ansel can't abide the thought of a wolf being killed by witches and signs on to help. Marcel needs Cami's help to keep Finn occupied while they rescue Oliver, but when she begins asking questions about his relationship with his siblings, Vincent begins getting curious about her intentions.
Just as Klaus is about to burn Esther's corpse, Elijah appears to him stating that perhaps it's time to listen to their mother. Elijah is an illusion projected by Esther in order to get close to Klaus. During their conversation, Klaus reveals that Mikael has been brought back to life and throws Kol under the bus. She tries to convince Klaus that once upon a time, both of his parents loved him, and all of their children.
She not only offers to kill Mikael should he threaten harm to her children, she also offers to give Klaus information about his biological father. She tells him the story of his parentage and offers to put him in the body of a wolf should he choose to accept her offer. He declines.
Esther gives Elijah back to Klaus and while Klaus is in the cemetery to claim his brother he encounters Ansel who has a connection to Klaus' past.