Gage Moon was the third and final child of Levi Moon and Abigail Moon. He had two older siblings, Becca Moon, and Danni Moon. He was conceived in the second part and born in Part 3: Baby Play Mat!.
Due to Abigail's questionable pregnancy LifeSimmer was not allowed to choose his traits, and he was given the loner and hydrophobic.
It took a few attempts because of the father (Levi Moon's) dislike of children. But, despite his dislike children trait, Levi takes part in raising him.