The mother, Yang Longying, of Chongqing, says it started when her second child, Xu Pinghui, had a fever when she was just eight months old. "Ever since then, she has been laughing uncontrollably," she told the Chongqing Evening Post.

The couple say the situation worsened when she reached two years old because she lost her ability to speak and could only laugh. The girl's father, Xu Weiming, a construction worker, has spent virtually all of his wages, plus extra money he has borrowed, for medical treatment but to no avail.

"Seeing her laughing, we feel even sadder than if she were crying," he said. A neurologist at Chongqing Medical College is now suggesting a brain scan to try and establish the cause of the girl's condition.

From the moment I picked up your book until I laid it down, I was convulsed with laughter. Some day I intend reading it. - Groucho Marx

Hoorah! A cure!

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