As the world swoons over Heidi the cross-eyed possum-that international darling of the Internet; the only marsupial with 150,000 Facebook friends and at least two theme songs on YouTube-critter-lovers back in her home state of North Carolina look on with horror.

Cross-eyed, my eye.

That possum is so fat her eyeballs are bulging out of their sockets, and she wasn't that way when we sent her across the drink.

Whatever they're feeding Heidi at the Leipzig Zoo, in the heart of the German state of Saxony, it's time to consider salads. Grass. Grubs. Earwigs.

And stop taking her picture! She might have thumbs on her hind feet, but she's not a circus freak.

"She's making the news because everyone thinks she looks cute," said Kindra Mammone, executive director of CLAWS, an exotic-animal shelter outside Chapel Hill, N.C. "But it's unhealthy. That's an unhealthy possum that's making the news."

Much like Paul the octopus, the German cephalopod who accurately predicted World Cup winners last summer until dying of natural mollusk causes, Heidi has grown into a four-legged heavyweight. Thanks to German news reports featuring Heidi with eyes akimbo, she soon won her own tribute page on Facebook, more than doubling fans drawn by the German chancellor.

"Das ist die Laune der Natur, finde aber Heidi echt suss," wrote one possum-liker, which translates roughly as, "This is the freak of nature, but I find her really sweet."

On the Leipzig website, which prominently features Heidi and her goonish grin, it is simply explained that she and two siblings "came from North Carolina (USA), where they were found as orphans and raised in a wild animal sanctuary."

The zoo also acknowledges Heidi's weight problem, which people there speculate could be the result of her American diet, and they promise to promptly correct with a high-fiber, low-energy regimen.

But if she's the possum North Carolina thinks she is, Heidi developed her fat-pressured eyeballs on the other side of the pond.

You already know about the critter with the oh-so-precious defect. This is the rest of the story.

Three years ago, the N.C. Zoo received nine opossums from several different sources-all of them connected with road-kills-and raised them by hand inside its wildlife rehab center. One year later, they were shipped by air to the zoo in Copenhagen, Denmark-free of any abnormality, ocular or otherwise.

"They wanted them," zoo spokesman Rod Hackney said. "In Copenhagen, this is an exotic species."

The N.C. Zoo has no idea what happened to them next. But according to the Copenhagen Zoo, seven of the nine world-traveling possums are still alive. Heidi and two others got transferred to nearby Odense, and then to Leipzig, but no one along her path wants to take credit for the weight gain.

But apparently, captive possums tend to grow roly-poly, and their eyes go askew. Possums are omnivores, but wilderness cuisine is more slimming. If a possum eats an egg in the wild, it's a bluebird egg, not a scrambled egg cooked in butter.

"I had a pet possum for the past two years that was cross-eyed from fat deposits," said Rob Vivian of Central Carolina Wildlife Rescue, serving Orange and Chatham counties. "When I saw the news, I said ... 'I should have put Opie on Facebook.'"

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The cruelest irony is that once a possum goes round in the belly, it's next-to-impossible to get the weight back off, and the crooked eyes are always the last consequence of obesity to linger. Mammone points out that Heidi is roughly 21/2 years old, more than halfway through the average possum lifespan.

Human beings are sometimes injected with Botox to correct strabismus, the clinical term for improperly aligned eyeballs. But if I were Heidi, fat and half a world from home, I'd ask for a jug of moonshine, the twang of a banjo and the solitude of a forest.