big dog hits baby in the head (youtube)

This dog is mouthing the baby like it would another dog, although gentle, this interaction is not safe and often leads to confusion and miscommunication once the dog begins to play rougher. The child will get bigger and then what? Will it be ok to mouth the baby then? Children this age MUST have a parent guiding their interaction to allow the dog space, and not challenge their tolerance. Notice the dog lifting his head to get away from the little girl as she is stepping on his paws to sit down IN HIS SPACE!?! Turn aways are often ways to ask for more space. What is this chld learning? i can sit on my dog and invade hs space. What is the dog learning? The child hurts me and crowds me and the adults don't help me.
What happens when the dog is hurting or just does not feel like he wants to be crowded? Then what?
It is always best to respect what your dog is communicating to avoid an uncomfortable situation for all. This dog should have been rewarded for signaling discomfort and the child should have been removed.