Artemis (Άρτεμις in Ancient Greek) is the goddess of the Moon and the Hunt. Her Roman counterpart is Diana. She and Apollo are known as the "twin archers."
History
She was born on the remote island of Delos. Her mother Leto had been running from Hera because she was angered about Zeus's affairs. Hera forbade her to give birth on terra firma (the mainland) or on an island. But the island of Delos was neither on the ground or on water; it was a floating island, so Leto gave birth there. She was born before her brother Apollo and helped her mother give birth to him. That is why she is sometimes considered the goddess of child birth. Artemis and Apollo were born as twins to Leto and Zeus. They grew up together.
At three years old, Artemis asked her father, Zeus, while sitting on his knee, to grant her six wishes. He loved his little daughter, and was very proud of her. She was his second daughter, and a bright and pretty child, and he agreed to grant her, her wishes.
Her first wish was to remain chaste for eternity, and never to be confined by marriage. She then asked for lop-eared hounds, stags to lead her chariot, and nymphs to be her hunting companions, 60 from the river and 20 from the ocean.
Also, she asked for a silver bow like her brother Apollo's golden one. He granted her the six wishes, also said that he promised to let her retract her wish to remain a virgin if she should wish it. Once Artemis grew close to retracting her virgin oath, when she met the hunter Orion. They slowly grew close, until Apollo, protective of his sister's virginity, had him swim out to sea to retrieve a floating target. Then, he tricked Artemis to shoot a distant, moving target, knowing his sister couldn't resist such a challenge. She did, and by this trick killed Orion, as the target was his head. In grief, she made him a constellation in the stars to always see his face.
Physical description(Greek and Roman)
She can appear as whatever she likes, but chooses to be the average age of her Hunters, which is around twelve. She has auburn colored hair and eyes as silvery as the moon, and is incredibly beautiful. Her cabin is number eight at Camp Half-Blood and since she is a maiden goddess, she has no children and it serves an honorary monument or a refuge for the Hunters when they visit. Her symbol was the silver bow and arrow, and stag.
Diana...
Personality(Greek and Roman)
Artemis cares deeply for maidens, as they are her kin. She has a group of female Hunters who she leads. She mostly detests men, and has little respect or liking of them. She is always at odds with her brother Apollo, as he always tends to flirt with her Hunters, and has in the past been responsible for the loss of her hunters by love. Despite this, there is great loyalty between the two siblings. Artemis is an excellent hunter, and does not have pity on her prey, or even her own Hunters if they fall in love and break their oath. Though she holds a deep prejudice against men, she is typically reasonable and willing to acknowledge them if they prove their worth, and also appears to have mellowed in her level of distate for other men in her camp and around her hunters, even keeping her contempt out of her voice and mannerisims.
Diana...
Powers
As the goddess of the hunt, Artemis probably possesses advanced hunting abilities such as speed, precision and the ability to disguise herself along with many other powers. She can also transform people and objects into things associated with hunting ( eg. once she turned a helicopter into a flock of birds). Because the hunting of wild beasts is within her domain, Artemis is able to help heroes more directly than other gods by saving them from powerful monsters if she wishes. She utilizes this loophole to bypass the ancient laws against direct interference and aid.
She may also have unspecified moon-related abilities, as she is also goddess of the moon. She possesses a silver chariot similar to Apollo's sun chariot, but it seems to be purely for transportation and she does not consistantly drive it through the sky as her brother does every day.
Artemis presumably possesses the standard powers of a God.
Children
The children of Artemis have many minor abilities. When in the moonlight all of their abilities are stronger and they heal their wounds. They have keen, discerning eyes that make them excellent archers, better than Apollo's kids. They are excellent at enchanting their arrows. All of Artemis's children are Athletic and good at sports. They also always know the position of the moon. Artemis doesn't give birth to her children, much like Athena. She bears them from the moonlight.
Children:
Roman Children: