They’re smart, hypoallergenic and have adorable faces that are designed to look forever young. They’re cava-poo-chons, and some have called them the ideal designer dogs.

The breed — a cavalier King Charles spaniel and bichon frise mix bred with a miniature poodle — is one breeder's attempt at creating a dog that maintains its puppy face.

With the help of a geneticist and veterinarian, the "triple-cross dog" was created by Linda and Steve Rogers of Timshell Farm in Pine, Ariz.

"There's always been a market for these forever-ish young dogs," trainer Steve Haynes, who’s working with 50 first-generation cava-poo-chons at Austin’s Fidelio Dog Works, told The Associated Press. "Until recently, specialized dogs like miniature Yorkies and miniature Maltese were the go-to dogs."

Although the American Kennel Club doesn’t recognize the dog as an official breed, cava-poo-chons have a loyal fan base. Fifty-eight families that purchased one of the puppies from Timshell Farm have returned to adopt a second.

But the dogs don’t come cheap — they range in price from $2,000 to $3,500.

The dogs weigh 10 pounds to 15 pounds and can live for 20 years. Timshell Farm offers buyers a choice of fur color, as well as two types of coat: curly or very curly.

However, some dog experts have said cava-poo-chons are simply the latest gimmick breeders are using to attract buyers.

For years Yorkies, Maltese and Pomeranians were popular, but they were replaced with “designer dogs” that have “cutesy names that end in '-oodle,' '-uddle' or '-poo,'" said animal behaviorist Darlene Arden.

"It doesn't really matter if it’s one of the infamous 'poo' breeds or a puggle, or any of the other mixes. Make no mistake about it: What you are buying is a very expensive mutt," Arden writes on her website. "Go to your local shelter, pick a mixed breed dog or puppy from there, save a life — call it anything you please, but save a life."

Learn more about cava-poo-chons in the video below.

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