A 12-year-old boy from the U.K., who had half of his brain removed, has made a miraculous recovery, according to his doctors.

Earlier this year Lewis Bull underwent surgery to treat a life-threatening disease similar to meningitis, The Sun reported. It’s called Rasmussen's encephalitis, which is a chronic inflammatory disease that usually affects only one hemisphere of the brain and occurs in children under the age of 10, the National Institutes of Health said on its website.

The condition is characterized by frequent and severe seizures, loss of motor skills and speech, paralysis on one side of the body, inflammation of the brain and mental deterioration.

Doctors warned his parents Mandie and John that Lewis could be confined to a wheelchair for the rest of his life, and even worse, they said that if the surgery failed to work properly, he could be stuck with the mental age of 12-year-old for the rest of his life.

Surgeons believed the best course of action would be to cut Lewis's brain in half. By disconnecting the swollen right side, they hoped the healthy left side would grow to compensate and take over key functions.

"He's doing fantastically well,” Mandie said. “He never complained or asked, 'Why me?' - he just got on with it. He takes life in his stride."

On April 14 Lewis underwent the six-hour operation at Great Ormond Street, and two days later woke up with half a brain.

And despite the doctor's warnings, he continues to make an astonishing recovery following three months of intensive physiotherapy and speech therapy.

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