Someone please explain this to me.

My brother came over today, and he brought over his dog, he has a 260 pound English mastiff, the dog is really sweet. But for some reason my four year old daughter didn’t want to be anywhere near the dog. they have met before at my brothers house, she was afraid then also.

why is this? she adores dogs, we have a border collie and they get along and play together just fine, even on day one when I first brought the dog home. My dog and my brothers dog are identical in terms of temperament. But she is just really scared of the mastiff for some reason. of course I respect my daughter and I make sure she feels safe. But why is she like this?

My brothers dog has done nothing wrong. Why is she acting so scared of him? Like I said we have a border collie at home and they play together.

Now my daughter does have dwarfism, she is four years old but only comes in at 2 feet tall and 25 pounds. I was thinking maybe that had something to do with it, but I really don’t know because we have an average sized border collie, My daughter is so small that she has to look up at the border collie, he weighs in at around 40 pounds and is way stronger than my daughter. and even from day one, she didn’t let the height strength and weight of the border collie get to her. So why is she so afraid of the mastiff?