Farm owner refuses to pay for puppies' expenses after guest's dog gets pregnant

A farm owner is refusing to pay for the expenses of puppies, after a guest's dog got pregnant on their property. The farm owner had two well-trained and socialized guard dogs, one of which was a male and not neutered for reasons related to the farming community. The farm owner's girlfriend invited her friend to stay with them while the owner was away on a work trip, and despite being told not to bring her dog, the friend brought the dog, who was in heat. The farm owner caught the dog trying to squeeze through a gap in the gate, and told the friend to keep her dog on a leash or go home. The friend left, but weeks later her dog had puppies. She is now demanding that the farm owner pays for half of the vet bills and puppy expenses, but the owner is refusing, stating that he told the friend not to bring her dog in the first place. Do you think the farm owner is in the wrong? Read on for updates on the situation.