I think the little girl and people like her have no concept that she should be cautious of the dogs so she walks in just like it's one of the dogs she's been raised around and it calms the dog. I think it scares a dog when someone is nervous around him.
I agree Josh. I KNOW it scares/bothers a dog when someone is nervous around em, any dog owner worth his salt can pick up on subtle changes in a dogs demeanor when he is uneasy/nervous. I TRY to always approach a dog calm and confident, i really think it makes a difference, hell and that applies to lots of animals not just dogs.