This gorgeous cat had always had the bluest eyes until about a year ago, one of his eyes began to change its color.

Meet Biggie the cat.

Biggie came to his family as a rescue stray. "Our neighbors found him as a stray and asked if we wanted to take him," reddit user rbend said. They couldn't say no.

Though he's a bit of a scaredy cat, once he's warmed up to you, he a very affectionate, loud purrer, and a big cuddler.

He always had a pair of stunning blue eyes until around early last year, the color in one of his eyes started to change.

It happened gradually over a year. His eye changed from blue to emerald green.

They have consulted two vets hoping to find out what caused the color change, but the vets couldn't find anything abnormal. "They said it's nothing. I guess it's something that happens with age.

"I'm not completely sure why it changed but vets have never been worried about it," rbend said.

Eye color change normally occurs in kittens. "Most kittens are born with blue eyes. As a kitten's sense of sight develops over the next several weeks, his eyes begin to take on a variety of other colors," according to vetinfo.

However, if an adult cat changes eye color dramatically in a short of period time, it can be a sign of eye damage or a serious underlying medical condition.

As for Biggie, he's a healthy and happy cat, and his eye color change remains a mystery.

"This guy just turned ten and he only gets prettier with age."

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