Due to my further writing on LucasForums using Kira, that character is a bit more complicated.
Kira was involved in the Sith back in the KOTOR time period. She was admired for her skill with a lightsaber, but something about her would not allow her to exercise the ruthlessness the Sith were best known for.
Before her eighteenth birthday, Kira was a Jedi apprentice named Teri Korr. She trained under her father, Ethan. Several days after Teri turned eighteen, her father was killed by a Sith Warrior. Her father's death drove her mad and she vanished, only to return as Kira.
A year later, Kira was involved in a crash on a highly unusual planet. She began to remember bits and pieces of her life as Teri Korr. As it turned out, the planet was split by a time barrier. When a fourteen year old Teri approached Kira, she remembered the planet.
Ethan and Teri Korr had crashed on the planet four years earlier and had been rescued two years later. Now, four years after the original crash, the planet had drawn young Teri face to face with what she had become. Kira knew she couldn't kill this young Jedi. If she did, she would die as well.
Just before Kira successfully escaped the planet, Teri was struck down by another Sith warrior, the same one who had originally killed her father. Kira felt weakness overcoming her. In an attempt to save her future self and return Kira to the light, Teri entered her future body, refusing to let it die.
Kira refused to listen to Teri, who became a second part of her brain. In the end, the body was killed, but Kira refused to let go of life. The two linked persons continued to enter new bodies and assume new lifestyles. Each time, Kira would destroy the original mind that lived in the body. This continued until they found Tanara, who was strong enough to resist destruction.
When the two found Elaina, Teri prevented Kira from killing her and the two found Tanara. When Tanara took Kira back, Teri stayed with Elaina and has not yet revealed herself.
I'm not entirely sure how I want this to go. From what I gather, Kira resurfacing will not be accepted at all, but it could be rather interesting to have Kira and Teri get into some kind of argument. If not that, Teri will resurface and ask a bunch of questions. For the most part, Kira's been restraining her. She's not sure how long it's been since she saved Kira's life.