Flippin big pittie the size of a rottie lol?
My cousin has a camp dog that looks simmilar, thing is theres plenty of rogue big ass lost dogs about that naturally mate with the natives.
And yeah the APBT was called the nanny dog well before the SBT was recognised in the 1930's can post a 1901 newsclip that says so lol. But I think its a real bad karma to attach that term to a breed, any breed of dog. I don't like it one bit.
Rock and that hard place, I don't have kids, So I cant respond to what I would do. But I do know that my kids would come before any dog.
If you find yourself going through hell; Don't stay. Just keep on going.