(WXIA) -- Little Tripp Halstead is back in the hospital Thursday morning.
Tripp's mother Stacy posted on Facebook that her son was admitted to Children's Hospital with breathing problems at around 5:30 p.m. Wednesday.
"We don't know what's wrong yet," Stacy Halstead wrote in the post. "Worst case scenario is that he is having seizures. Best case is that he has pneumonia."
Tripp suffered a severe brain injury after being hit by a falling tree branch at his daycare center. Earlier this week, the family marked the one-year anniversary of the accident and Tripp's recovery with a trip to the Georgia Aquarium.
MORE TRIPP HALSTEAD
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