Charlie and Spike are two kittens with Myotonia Congenita, otherwise known as ‘Fainting Goat’ syndrome. At the slightest sound, the kittens respond by collapsing and falling into a rigid paralysis that lasts about a minute before they return to normal. This condition has hardly ever before been diagnosed in a cat, is rarely found in dogs, and is more common in goats. The kittens are able to walk, but they cannot run or jump. Aside from this, they are normal.
UPDATE: Sad news, the two fainting kittens have died of respiratory failure. Here’s a memorial video.