I don't know. My father had a German Shepperd when he was young, but one year it turned on them and they put it down.
I had a yellow lab, which is considered a very peaceful breed. But it was very hyper and it bit me once. We got rid of it because we had young kids.
I also had some dogs, that I played too rough with, when they were young.
I think with kids, it's better to go small, beagle size or less. But the most important thing is to keep in perspective, that it's a dog. And if it shows signs of being agressive, you don't take the chance.
Now we have an older Shepherd/Chow/Retriever mix. It's an older dog, so I know the day is coming that we will need to get another dog.