if hes determined and wont quit. hes probally game. most likely he will end up being the best dog you have. if hes skinny worm him and take him to the vet for a fecal and to get him shots. some pits are lean and some are bulky. the pig hunting/pig stalking he will love you just give him a minute. my dogs hunted and preyed oon chicken for a long time. and hogs they dont stop untill they are done. my house pitt has been down on a boar for more then 3 hours going round after round without giving up. then came home got her bath and curled up on the couch with our cat.... just make sure your son is good to his new found friend and get a chip or a gps collar because if he found her wandering shes probally a wanderer.....please dont take the dog to the shelter because the outcome is never good for a pitbull no matter how sweet it is