So we are having some major problems with our boy Bentley. He is about 4 months old and we have him living with our 9 year old female GSD. They have had their puppy/adult run in's and we thought that would teach him. However he will not learn to leave her along...constantly nipping at her, walking into her, jumping on her, barking at her. He does it in a playful manner, but she has corrected him numerous times some times causing small injuries even. Well this morning he jumped on her again while going out the door and got bit on the snout requiring a few stitches. We exercise them multiple times per day, we have leashed him to pull him away anytime he isn't respecting her, but nothing works. Even after he got bit this morning he was going right back after her. We are at a loss, but we don't want our puppy to keep getting hurt nor do we want our adult to have to keep defending herself like this. Any ideas or are we at the point where we may need to find the puppy a new home?