Kiefer was born to Geb and Candice Adamson. Soon thereafter, she got pregnant again, and gave birth to Kiefer's younger brother, Ryan. The stress of having two kids built up, and she ended up having to give up Ryan, and sent him to an orphanage. Kiefer was only four years old, with Ryan only one year old at the time.
Kiefer was the only child, or so he thought. He was raised up by his mother alone, and kept asking where is his dad. The house was only filled with pictures of the two but he kept asking on one picture in which another baby boy was beside him. His mother lied that the baby boy was his cousin, in which he took on easily. Upon entering school, he was serious and quiet, but as he entered middle school, his attitude began to change. He likes to go home a bit late, go on rackets with his friends and even go out on weekends, which partly affected his grades so he was grounded for a month.
He isolated himself in the four corners of his room, with his TV, books and iPod Shuffle. He thought it was just a normal event in a young teenager's life, but oh no. One day, he heard his mother mentioning a name. It was Ryan's name. He asked him who's the Ryan he's talking about. This time, he's very suspicious of her and forced her to tell her the truth. She eventually flooded him with the full details of his younger brother, why he had to put him in an orphanage instead of letting her live with him in the house. This left him enraged. He quickly packed his bag and resisted his father's pleas. Using the share he had in their rackets, he left home in search of his long lost younger brother.
He took a bus going to... somewhere. He didn't cared on what will happen to him as long as he finds Ryan. Unfortunately, he slept during the trip and eventually he was lost. He didn't know the area but from the looks of it, he's out of the town. He began to get scared. He was hungry, thirsty and had no sense of direction. The conductor kicked him out because the location was not enough for his fee. Upon getting down and the bus revving the engines again, he saw someone. No, not someone, something. It was a monster, armed with sharp claws. He began to run into the fields and then into the wilderness. The monster charged after him, ready to swipe its claws. He wasn't looking on where he was looking and he bumped his head on a log hard, making his forehead bleed. He went down for the count.
He thought he was dead. He opened his eyes and he was in some kind of cabin. Some people, demigods, were looking at him. He asked where he was and they explained it thoroughly that he was a demigod and he's at Camp Pyramid. Afterwards, he was claimed by Geb, his father. From then on, he swore to himself to train his best and find Ryan.