Susan and Mary Test (The Test Twins - Johnny Test)

They're 18-year-old twin super-geniuses who create advanced technology, usually, for their brother, Johnny. While both are brilliant, ambitious, and obsessed with their neighbor, Gil, they have distinct personalities: Mary is the older, more empathetic, level-headed, and open-minded twin, whereas Susan is the younger, more abrasive, tomboyish, and strict, fact-based scientist. Mary Test (Older Twin)

• Personality: More empathetic, sympathetic, and level-headed than her sister.
• Scientific Approach: Open-minded; often explores theoretical, sci-fi, or,,,alien-based concepts, which sometimes proves right.
• Traits: More "girly" in her interests compared to Susan.
• Relationship to Johnny: Generally nicer to her brother, though still uses him as a test subject. Susan Test (Younger Twin)
• Personality: More,rude, tough, brash, and,short-tempered than Mary.
• Scientific Approach: Strict,,fact-based, and,logical, often acting as a skeptic to,Mary's,theories.
• Traits: More tomboyish and firm.
• Relationship to Johnny: More likely to get annoyed and explode at Johnny. Both sisters work together in their lab at the Porkbelly Institute of Technology, frequently acting in unison due to their shared high IQ, despite their differing approaches to science and life.