We have coyotes and foxes in our neighborhood and in foxes in our mountain neighborhood. If you do nothing it will leave on its own. I don't know about fox but when coyote packs are removed new packs move in. I've not heard of fox going after dogs but do know that coyote will kill small dogs and cats. Do not leave any kind of food (bird, pet food etc.) outside as that will keep them around and keep garbage in tightly enclosed containers. We are told to make loud noises, throw pebbles, not rocks or put pebbles in a can and shake it anything to scare coyotes and foxes away. The foxes were probably there first and are losing their fear of humans. Anything you can do to make it fearful will keep it away and most likely save its life. It probably has a den somewhere nearby, not sure what their range is, and will leave on it's own.