The hereditary and genetic background of a person. The "Jeams" are what makes a person act a certain way.
Cory: "Why are you such a lunatic all the time?"
Paige: "It's not my fault! We got double-teamed from both sides of the family!"
Cory: "Not on my side!"
Paige: "Dude, it's in my jeams!"
Cory: "Oh.."
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