Mini, Adorable Puppy Smaller Than iPhone, May Be Britain's Tiniest Dog (PHOTO)

When diminutive puppy Mini was born, her owner didn't think she would survive.

At birth, the tiny Yorkshire terrier Chihuahua-cross weighed no more than an egg and could fit comfortably on an iPhone, with room to spare. Mini's owner, Emma Williams, fed the pup milk formula through a straw every two hours to boost her chance of survival, the Daily Mail notes.

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"At first I wasn’t sure if she would make it because she is so small and she kept being pushed out of the way by the others," Williams said. "But she’s a strong little thing."

Now Williams, a 29-year-old senior accounts manager from Dorset, England, said she believes Mini is Britain's smallest dog.

"I took her to the vets and they hadn’t come across a puppy so small," Williams said. "And when I researched online I couldn’t find one either."

The heartwarming pictures, which are featured on the Daily Mail, show Mini with her siblings, as well the pup cradled in her mom's mouth. The images certainly help make the case for Mini as one of the world's cutest puppies, although the dog is sure to have competition from this adorable puppy perched in a pint-sized chair, as well as these tiny little pugs having a bath.

Across the pond, though, Mini will be challenged for the title of tiniest puppy ever by a California dachshund mix named Beyonce. Born in March at an El Dorado Hills animal shelter, Beyonce was so small she could fit in a spoon and had to have mouth-to-mouth performed on her by veterinarians before she started breathing.

According to the Guinness World Records, the smallest living dog (determined by height) is a long-haired Chihuahua named Boo Boo. The pup from Kentucky measured 4 inches tall in May 2007.

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