I am wary of unfamiliar dogs because, well, sometimes they bite. I don't want anyone getting in my dog's face because, while she's never ever shown any inkling of biting, she is a dog. 
There's not enough info in this story to determine who was where when the bite occurred. I feel bad for the woman and I'm glad that it wasn't one of the kids. 
Dang, DG! Busted leg bone? I've been chomped a few times. Broken skin, nothing traumatic. 
Dogs - they bite.