The Cavalier King Charles Spaniel is a small breed of Spaniel-type dog, and is classed as a Toy dog by most Kennel Clubs. It is one of the most popular breeds in the United Kingdom. Since 2000, it has been growing in popularity in the United States. It is a smaller breed of Spaniel, and Cavalier adults are often the same size as adolescent dogs of other spaniel breeds. It has a silky coat and commonly an undocked tail. The breed standard recognizes four colours (Blenheim, Tricolour [black/white/tan], Black and Tan, and Ruby). The breed is generally friendly, affectionate and good with both children and other animals.