It is extremely rare for a Golden to do this. There must be more to the story.
The most popular breeds are always higher on the bite numbers. Labs are the most commonly-reported breeds for dog attacks in many areas, but they aren’t nearly as newsworthy as other breeds, even though they can cause just as much damage. I will say, though, that keeping dogs outside without interaction can make them dangerous. Socialization is extremely important, no matter what breed of dog you have. In addition, a three-year-old should not be anywhere unattended, especially around a dog.