Pearl, a 2-year-old Chihuaha, has been officially named the world's shortest living dog by Guinness World Records. She is 5 inches long, shorter than a Popsicle stick at just 3.59 inches tall, and weighs 1.22 pounds - a huge gain on the less than one ounce she weighed at birth. Her owner, Vanesa Semler, said she is "blessed to have her" and Pearl has become an internet sensation, with thousands of people around the world celebrating her achievement.