Kittens usually are born with blue eyes. Their eye pigment starts to change at around 8 - 12 weeks of age. The change of eye color could indicate the age of a kitten. By 4 months of age, a kitten's eye coloration should mature into adult color.
Some cats can develope 2 different eye colors, called odd-eyed cats. It occurs mostly in white cats, but can also be found in other colors of cats. The cause of odd-eyed coloring is genetic. The odd-eyed cats are most noticable in Turkish Van, Turkish Angora and Japanese Bobtail.
There is a misconception that most of the odd-eyed cats are deaf. The truth is that 60% - 70% of odd-eyed cats retain normal hearing while 10% - 20% of normal eyed cats are born deaf or become deaf as they age.
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