What was reportedly an isolated, unsocialized, untrained, probably sexually intact dog with a history of aggression (reportedly seven prior bites), tethered on a very short leash, no food, no water, not taken out to relieve itself so forced to stay in its feces and urine, while what is probably its mate and its puppies roam the house....kills a child.
Owner of the dog kills the dog for killing the child.
So, a child and a dog are dead due to the dog's owner, who is also the child's father.
This is not and never will be a matter of dog breed or type. This appears to be a combination of cruelty to an animal, irresponsible dog ownership, and negligent parenting.
Read about it here and here.