The Yorkshire Terrier is one of the smallest dog breed of terrier type, and of any dog breed. It has a grey, black and tan coat, and the breed's nickname is Yorkie. Yorkshire Terriers are very playful and energetic dogs. Many people who have a Yorkie as a pet have two, because they often have separation anxiety when left alone and 'they don’t enjoy being alone.' . It may take three or more years for the coat to reach its final colour. The final colour is usually a black or greyish colour. P. H. Combs, writing in 1891, complained about show wins awarded to puppies, when the dog's coat does not fully come in until three or four years old, 'and the honour of winning such a prize (for a puppy) can therefore be of but little practical benefit to the owner' since the adult dog's colour cannot be exactly predicted.