Lullabye

Lullabye is an original fictional character who first appeared in New Mutants: Last Class.

Background
Kiona Kinney first displayed her mutant power at the tender age of 5. Exhausted after a long lunch hour spent building snowmen versions of the Avengers with her friends, a drowsy Kiona nodded off in the middle of a lesson and simultaneously released enough sleep-inducing pheromones to put her whole class out for the better part of an hour. When she awoke, she found that she could not rouse her teacher nor any of her classmates, and began to panic. As she wandered the school in search of help, everyone she came across promptly grew weary and slumped to the ground in a deep, peaceful sleep.

Realizing that she was the cause, Kinoa willed her power to stop and managed to wake everyone up, but the damage was already done. The event was all over the news in her home town of Matteson, Illinois, with some headlines going so far as to characterize it as an "attack". Her school would not allow her back and even her own parents feared what might happen if their daughter's power triggered again in a more dangerous situation. What if she put them to sleep while they were in the car, or cooking over the stove?

It wasn't long before Kiona was sent to the Xavier Institute, a school for young mutants such as herself. Being separated from her friends and her family was a shock, but her parents promised to visit her regularly. Most importantly, her new classmates and teachers did not fear her - in fact, many were far stranger than she was, or at least they seemed to be on the outside. With a little guidance, Kiona quickly learned to fully control her power, learning to turn it on or off at will, without any accidental outbursts.

Kiona made friends quickly in the Lower Class, particuarly among the social pariahs, such as "Sunny" Ahn Myung Sun, and later Vivian Meeks, both of whom were frequently the subject of teasing and bullying. She was not afraid to break the school's rules concerning the use of powers on classmates if it meant coming to a friend's defense, and soon earned a reputation as something of a school yard vigilante. Her signature move was to drop a bully into a deep sleep, then draw on their face with permanent marker. The detention was so worth it.

New Mutants: Last Class
Kiona was one of only a few mutants in the Lower Class to keep her powers after M-Day. School was never quite the same after that, and even when new mutants began to reappear two years later, most of them were highschoolers anyway. Still, the hope for the continuation of the mutant species brightened moods all over the school, and the influx of new faces provided more than a little excitement. In particular, Kiona and her friends developed quite the group crush on Nathan Jacobe, blissfully ignoring the fact that he was half again their age and already had a girlfriend.

Timeskip and the Last Stand
Kiona was only 11 by the time that the war between the Purifiers and the X-Men culminated in the climactic battle known as The Last Stand of the X-Men. Led by Anole, she and the rest of the Xavier Institute students were teleported to safety - not just to Wakanda, but a full two weeks into the future. Her teachers and mentors were gone, and even her family was out of reach thanks to the Superhuman Registration Act that passed soon after.

But not everything was lost. Kiona still had her classmates and friends, and she did her best to rally around them. Though her mutant power was easily innocuous enough to allow her to live in the United States in hiding, she refused to abandon her less fortunate friends. She remained in Wakanda with Sunny and Vivian and proudly became a founding member of Unity, earning her the codename "Lullabye".

Powers and Abilities
Kiona is a Beta-level mutant. Her body is capable of giving off large quantities of powerful sleep-inducing pheromones at will. These pheromones require up to a minute to take full effect, but are colourless and odourless, making them difficult to detect.

Naturally, Kiona is immune to the effects of her own pheromones, and subsequently most other drugs or effects that cause drowsiness or induce sleep. None the less, she still sleeps naturally and maintains a normal human sleep cycle.

Kiona is also a talented singer and has had comprehensive training in self defense and hand-to-hand combat.