Katherine is the daughter of John Stewart one of the Green Lanterns. Katherine's mother is a normal human. She was born April 7th, 1994.
Katherine does not come off as a hero, he personality typing her as more of just arrogant. She doesn't care much for others, and keeps to herself, or rather he sketch book. To her, though, the personality of a hero does not matter. As long as they fight for the sake of good, and try their best to destroy evil, and have a dream of a world without it, then they are an hero. So underneath her vain, spacey, and somewhat rude, shell is a caring person, she just thinks big, and hates to deal with the little things. In the end, this mind set is what makes her an effective hero, and while she can be cold, she is usually the level headed one in the group.
She is a very artistic person, she dabbles in most forms, but prefers the mobility of a sketch book and pencil. The attention to detail and creativity involved in this is the main factor of her success. This love to detail is a main reason she comes off as cold, because she is always pre-occupied adding the final touches to a project, and finds it more important, though even without it she hates to hear people whine to her.
Like other Green lanterns, her power is completely dependent on her ring. At this point she only has a training ring, which has limited power, but easier to control. Eventually she will be able to make large objects, such as a fist made of it, and the more she concentrates, the more solid it is. The power is completely reliant on imagination, and so the limitations depend one th person wearing the ring. At first she may only make small objects, best with close range, but mostly useless. Although weak at first, the ring is less of a drastic boost every once and awhile, and more a low incline upwards. The more she uses it, and the harder she concentrates the faster she will grow with it. Eventually she can even fly with it's powers.
The biggest draw back is that the ring must recharge, as the ring's power increases the less 'battery' it will have, and the more she will have to recharge it. Once the power goes out she is useless in battle. The charger is large and bulky, as well, so bringing it into battle is difficult.