Small, sweet-tempered and sporty, the Cavalier is one of the most popular dogs in the world. These cute, energetic and gentle dogs are ideal for families, and are very trainable. Horses sometimes suffer from separation anxiety, so they should not be left alone for long periods of time. They also need daily exercise to keep them fit and prevent them from getting bored, as a bored Cavalier can be destructive. Be sure not to take them outside during the hottest part of the day, as Cavaliers don't always do well in hot weather.