The Cavalier King Charles Spaniel is a small spaniel classed as a toy dog by The Kennel Club and the American Kennel Club, that originated in the United Kingdom. Since 2000, it has grown in popularity in the United States and ranks as the 18th most popular pure-breed in the United States (2013 Registration Statistics). It has a silky, smooth coat and commonly a smooth undocked tail. The breed standard recognises four colours: Blenheim (chestnut and white), Tricolour (black/white/tan), Black and Tan, and Ruby. The breed is generally friendly, affectionate and good with both children and other animals; however, they require a lot of human interaction. Since they are a family dog, it is recommended to not leave them alone for long periods at a time. The expected average lifespan of a Cavalier King Charles Spaniel is under ten years.