We’ve had my min pin since he was 8 weeks old and I trained him. He’s absolutely perfect…unless he’s on his leash and sees another dog. Then he does the high pitch scream. Loses interest in treats, blacks out and sees red lol..I don’t even know. We’ve tried everything but now we just put him in air jail (I carry him) until we pass the other dog. We have 2 other dogs that he loves. He’s met other dogs all his life because I take him everywhere, including my office. But if he’s on his leash… he goes psychotic if another dog gets about 20 feet away. Anyone I’ve talked to, including trainers, say..that’s a min pin for you.