Boo Boo, the smallest dog in the world

Boo Boo:

A tiny dog from America called Boo Boo has been named as the smallest pooch in the world.

At just four inches (10.16cm) tall, the Chihuahua is the world's smallest dog in height, according to the Guinness Book of World Records.

Boo Boo's owner, Lana Elswick, breeds Chihuahuas, and said Boo Boo was the size of her thumb when she was born.

Mrs Elswick told an American newspaper that the Chihuahua is a total diva, and her favourite food is crisps.

Boo Boo hasn't got much bigger since being born a year ago, weighing just 42.5 grams (1.5 ounces).

Mrs Elswick explained that she had her dog measured in May, but didn't send it to world record bosses until June.

She found out that Boo Boo was the smallest dog in the world on 10 September in an email.

The tiny dog is about the same height as a mobile phone.

What happened to the dog, has the dog been in an accident that caused him to become so small?
Why is the dog so small.
How can the dog survive when it was born according to the size.