A 2-year-old girl from Calhoun remains hospitalized after what began as a routine case of the flu developed into a rare neurological condition that left her unable to move her arms and legs, her mother tells CBS News Atlanta.

Kenia Lopez says her daughter, Sarah, tested positive for Flu A more than two weeks ago. At first, doctors sent them home from the hospital with instructions to monitor her symptoms. 

But by the next morning, Lopez says the toddler's condition had dramatically changed. "She wasn't sitting up at all. She would just fall to the side," Lopez recalled. "She couldn't move her legs anymore." Lopez rushed her back to the emergency room, where an MRI revealed a diagnosis of transverse myelitis, a rare inflammatory disorder affecting the spinal cord.

Doctors ruled out autoimmune or preexisting conditions and believe the sudden onset was linked to complications from the flu. While transverse myelitis affects roughly 1,400 people in the U.S. each year, experts say it remains an uncommon outcome of a viral infection. 

Dr. Marjada Faith Tucker, a general medicine physician not involved in Sarah's care, says the condition can occur after the flu but is not directly caused by it. "It's not something parents should be alarmed by, but rather informed," Tucker said, adding that most patients recover with consistent physical therapy.

Lopez describes her daughter as an energetic, talkative child who speaks both English and Spanish. Now, the family is focused on helping her regain strength and mobility. "She was a very active 2-year-old," Lopez said, hopeful that ongoing therapy will help Sarah return to her normal self.

Lopez says Sarah is expected to be transferred to Children's Healthcare of Atlanta's rehabilitation program later this week to begin physical therapy.