How do we teach her to stop? She is 4 months old. When we go into the yard (not always, but seems to be more and more as time goes on), she jumps on us and growls at us. She is trying to nip when she jumps. She runs all around us doing this. We can't even walk across the backyard. We can't catch her to make her stop. We firmly tell her NO, but it doesn't seem to stop the behavior. She doesn't do this while in the house. Any thoughts or ideas?