Frank and Louie, despite having two names, was just one cat.
He had one brain, but possessed two near-separate faces, each with its own nose and mouth.
Both mouths were connected to a single oesophagus, although only one of the mouths was functional; the other had no bottom jaw.
He had three eyes, but the ‘shared’ central eye was blind and did not blink.
‘Janus cats’ such as this rarely survive more than a day following their birth, however, Frank and Louie lived a remarkably long life.
He was born on 8 September 1999 and died on 4 December 2014, aged 15 years 87 days. This made him the longest-surviving Janus cat ever.
The term ‘Janus cat’ was conceived by Dr Karl Shuker, a British zoologist who moonlights as a life sciences consultant for Guinness World Records.
“Cats such as Frank and Louie, born with two faces, suffer from a developmental abnormality known as diprosopia, in which the face widens and partially duplicates during embryogeny due to the excessive production of a specific protein called SHH,” Dr Shuker explained.
“The technical term for such a cat is a diprosopus, but as this is not the most readily pronounceable term, however, when I first wrote about such cats over a decade ago, I coined for them the term 'Janus cat', named after the Roman god of doorways, Janus, who had one body and one head but two faces, just like these cats."
Frank and Louie was owned by Martha “Marty” Stevens, a veterinary nurse from Massachusetts.
She was working at Cummings School of Veterinary Medicine at Tufts University when Frank and Louie’s breeder brought him in to be put down.
Marty took pity on the one-day-old kitten and decided to rescue him, although experts warned her that he was unlikely to survive very long.
Frank and Louie could not feed himself at first, so Marty tube fed him with a special formula for three months until he learnt how to eat on his own.
Starvation is one of the leading causes of death for Janus cats, who can find eating difficult due to the congenital defects they suffer from.
For those first three months, Marty also brought Frank and Louie to work with her, as the young kitten required constant care and attention.
Frank and Louie went on to defy all odds by living a long, healthy life.
Over time, he became strong enough to start playing with other cats, and he formed a special bond with the family dog.
Marty described Frank and Louie as “very, very laid-back, not afraid of people, very friendly, and he's actually more of a dog than a cat. He walks on a leash; he goes right in the car - he loves car rides.”
After featuring in Guinness World Records 2012, Frank and Louie became an internet celebrity, appearing in countless news articles and videos.
Sadly, in 2014, Frank and Louie was euthanized as he was suffering from an aggressive form of cancer.
"He was 15 years old; an incredible age for a Janus cat, far surpassing all previous examples and likely never to be surpassed by any in the future,” Dr Shuker said at the time.
“A wonderful testament to the love and devotion that Marty had always given to him throughout his long and happy life with her. Rest in peace, Frank and Louie.”
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