At many points in the game, the New Kid will have to meet up with the Coon, who will give him a superhero class and then show him through his Origin Story. At the end of the Origin stories, the New Kid finds Kelly having sex with Chris. The Coon fails to understand this is a common thing that happens to all people and makes this the New Kid's horrific backstory.
Each day ends with the New Kid coming home to find his parents arguing with each other. Chris berates Kelly for giving information to the School Councillor and the School Principal about the New Kid's race and sexual ethnicity after the talks. Chris is angry because he wants to keep the New Kid's real backstory private. They then act calm when they see the New Kid, and go in the bedroom to fight.
When travelling through Mephesto's lab, the New Kid finds a room, where both Chris and Kelly are locked up. To pass through to the next room, the New Kid needs DNA from one of the parents. This involves either cutting off Chris's head or Kelly's arm, both of which will result in one of them dying. The New Kid then puts the head/arm in the scanner and can pass through.
In "Farts of Future Past", the New Kid finds himself going back in time to the Origin story. He goes into the parents' bedroom, where, after seeing 2 versions of his child, Chris explains the New Kid's backstory. He explains that, when he was younger, he made a Facebook page, and managed to get 3 million followers within 3 hours. Scientists kidnapped him and Kelly and did experiments to see how their powers work. The two then fell in love and gave birth to the New Kid. They had to run away, moving from town to town, until they got to South Park. After telling the New Kids and the Coon this, they feel better and decide to live happily.
The skin color and hair color of Kelly depends on the skin and hair color of the new kid. Kelly wears a green shirt and black pants.
Kelly seems to be the kinder of the two parents. At the start of Stick of Truth, she suggests the New Kid makes friends, while Chris kicks the New Kid out of the house. She, with Chris grounds the New Kid when he is not in bed on time.
Kelly is a concerned mother to the New Kid, who often cares for the New Kid. She does not seem to get irritated by the New Kid's silent nature. Kelly is protective over her son, worried that people will find out about his background and eventually lock him up again.
In The Fractured But Whole, Kelly and Chris are seen fighting each other. When Mr. Mackey speaks to Kelly for clarification about the New Kid's sexual orientation, Chris berates her, worried people will find out the truth. This then continues until they argue all the time. Even in The Many Asses of Dr. Mephesto when The New Kid has to make a decision of who to kill, the two yell at each other from across the room and try to persuade the New Kid to kill the other one. When they tell him the truth, the two feel better and make up with each other.