In short order, Teddy—a bright-eyed and bushy-tailed 3-year-old yellow Lab—punched a wall button with his nose, yanked a rope to open a kitchen cabinet door and tugged a walker across the floor. After ...

The public information officer squatted on the concrete in slightly flared jeans, her pin-straight hair parted in the center, and cooed at the dog like she was a pigeon. The dog's ears perked up, and ...