Although they’re born to be a companion, the Cavalier King Charles Spaniel dog breed retains the sporty nature of their spaniel ancestors. If they’re not sitting on a lap or getting a belly rub, nothing makes them happier than to flush a bird and then attempt to retrieve it. This small but sturdy dog stands 12 to 13 inches at the shoulder and weighs 13 to 18 pounds. There is no such thing as a “toy” Cavalier, and you would do well to avoid buying a Cavalier from a breeder who offers dogs half that size. Cavaliers are adorned with medium-length coats that are silky to the touch and may be slightly wavy. Adult Cavaliers have feathering on their ears, chest, legs, feet and tail.