Baby KJ was a pioneer before he was even a year old. Born in 2024 with a rare, life-threatening genetic mutation, Nicole and Kyle Muldoon’s son is the world’s first patient to receive successful personalized gene editing therapy. Doctors at the Children’s Hospital of Philadelphia (CHOP) and Penn Medicine collaborated to create a unique drug just for KJ, to treat his disorder known as severe carbamoyl phosphate synthetase 1 (CPS1) deficiency. After spending the first months of his life in the hospital, KJ’s medical breakthrough came with his first dose in February 2025 when he was 6 months old.

Now, a busy toddler and youngest brother, KJ is a piece of medical history – and he just started to walk.

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Learn more about rare disease – and what to do in a diagnosis – at the National Organization for Rare Disorders: https://rarediseases.org/

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BONUS The Path with Becky Quick: Head of the Class 3/20/26

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BONUS The Path with Becky Quick: Head of the Class 3/20/26