Norbert is a fluffy, 7" tall mixed breed registered therapy dog, best known for his Norbert picture book series, and his popularity on social media.
 Norbert's breed is unknown, but is suspected to be a cross between 3 dog breeds, chihuahua, cairn terrier & lhasa apso.
 Norbert's time, money and book revenue is given to various charitable causes throughout the United States.
Tracheal collapse in dogs is a condition characterized by incomplete formation or weakening of the cartilaginous rings of the trachea resulting in flattening of the trachea.
 It can be congenital or acquired, and extrathoracic or intrathoracic (inside or outside the thoracic cavity).
 Tracheal collapse is a dynamic condition.
 Collapse of the cervical trachea or extrathoracic (in the neck) occurs during inspiration; collapse of the thoracic trachea or intrathoracic (in the chest) occurs during expiration.
 Tracheal collapse is most commonly found in small dog breeds, including the Chihuahua, Pomeranian, Toy Poodle, Shih Tzu, Lhasa Apso, Maltese, Pug, and Yorkshire Terrier.
The Cane Corso (pronounced kah-nay kor-so ] ) from Italian "cane" (dog) and "corso"from the Latin "Cohors" meaning "Protector", also known as the Italian Mastiff, is a large Italian breed of dog, for years valued highly in Italy as a companion, guard dog, and hunter.
Princess is a Flash animation series by Matt Stone and Trey Parker, the creators of "South Park".
 The story follows a Lhasa Apso dog.
The Cane da Presa Meridionale (Italian for "Southern Catching Dog") is the old, "functional" working variant of the Neapolitan Mastiff.
 Before 1946 there was no distinction between Neapolitan Mastiff, Cane da Presa and Cane Corso, these were simply three different names for the same dog.
 The modern Neapolitan Mastiff is unlike the original, a dog created by dog shows. Fans of the original Mastino have started an organisation which is trying to gather the remaining specimens which would fit the 1946 standard of the Neapolitan Mastiff.
The Tibetan Spaniel is a breed of assertive, small, intelligent dogs originating over 2,500 years ago in the Himalayan mountains of Tibet.
 They share ancestry with the Pekingese, Japanese Chin, Shih Tzu, Lhasa Apso, Tibetan Terrier and Pug.
The Lottatore Brindisino is a breed of dog used for dog fighting originating in Brindisi, Italy.
 The dog was created by selective breeding the Cane Corso, Rottweiler and Pit bull.
Ch.
 Zentarr Elizabeth (2005-2017), also known as Elizabeth, is a Lhasa Apso show dog bred and handled by Margaret Anderson who won Best in Show at Crufts in 2012.
 She also placed third at the Eukanuba World Challenge in 2011.
The Kinnaur Sheepdog, also called the Apso Do-Kyi (tied-dog), is a large Apso.
 Apso is, in Tibetan, short for "Ara" meaning "moustache" and "sog-sog" meaning "hairy".
 These are profusely hairy dogs having an elongated body with front legs shorter than the hind ones, dropping ears and curly tails.
 They are related to the smaller Lhasa Apso, as well as the intermediate size Tibetan Terrier.
The Lhasa Apso ( ) is a non-sporting dog breed originating in Tibet.
 It was bred as an interior sentinel in the Buddhist monasteries, to alert the monks to any intruders who entered.
 Lhasa is the capital city of Tibet, and "apso" is a word in the Tibetan language meaning "bearded", so, Lhasa Apso simply means "long-haired Lhasa dog".
 There are, however, some who claim that the word "apso" is a form of the Tibetan word "rapso", meaning "goat-like", which would make the equivalent translation "wooly Lhasa dog".

Question: What do Cane Corso and Lhasa Apso have in common?
Answer: dog breed