Foxes are not cuddly gorgeous creatures, they are a damn menace. A few months ago they cleared out my hens...very sociable.
JRT's are bred for killing vermin and like most dogs will do so if they get the opportunity. My old sheepdog loved to kill rats and the odd chicken if he got a chance, he never turned on a human though, not his nature.
Just be careful about what has access to your garden but if a cat gets in, it really isn't your problem.
Dog bite incidents with children are usually the fault of the parents. My son has been bought up with dogs and is not afraid of any of the 4 we currently have, however he has been told never to go near a strange dog, it's common sense. If his freinds or anyone new comes to the house, I put the dogs away, again common sense.
Stop blaming the dogs.