(NBC News) A medical mystery is unfolding in California, where several children are experiencing paralysis in their limbs.
It's only when 4-year-old Sofia Jarvis walks that you can tell something is wrong with her left arm.
It's been paralyzed from a polio-like condition. ...
It's only when 4-year-old Sofia Jarvis walks that you can tell something is wrong with her left arm.
It's been paralyzed from a polio-like condition. ...