Boston Terriers are native to the United States, originating in - you guessed it - Boston. A people-loving, lively breed, Bostons are known for their expressive faces and amusing sense of humor. They are eager and easy to train, and are excellent with children. These friendly, sturdy dogs are content to be around their people, have a medium energy level, and overall make excellent companion animals. An average-sized Boston Terrier typically weighs around 25 lbs. when fully grown.