i've been thinking about this some more, and i don't think using examples of other breeds of dogs in this thread is useful. a pitbull is a pitbull. it is a whole nother kettle of fish. this is not a regular dog we are talking about here.
i think you have a responsibility to your community to sort this issue out. it might not be your dd that is hurt, but it may be someone else's child.
is your dog registered with the council?