One of the big reasons your older dog probably isn't doing anything about it yet because your younger dog is under 6 months, therefore gets the "puppy pass" from your older dog.
I personally would suggest a time out. If Charlie starts playing too roughly pick him up (or lead him if he's too big) to another room and close the door, or gate him off. Don't pay attention to him for a bout 5 minutes, then bring him back. If he starts playing too rough, do it again. Eventually he should learn. Also, ensure he is getting enough walking exercise, mental stimulation (training), and toy time with a person.
Saying "No" doesn't really help because it's not redirecting the behavior. When something like this happens, making a physical correct, or even shaking a can of coins isn't really the way to go. Try redirecting the game with a toy, or giving the time out if that's not working.
Best of luck! =]
I personally would suggest a time out. If Charlie starts playing too roughly pick him up (or lead him if he's too big) to another room and close the door, or gate him off. Don't pay attention to him for a bout 5 minutes, then bring him back. If he starts playing too rough, do it again. Eventually he should learn. Also, ensure he is getting enough walking exercise, mental stimulation (training), and toy time with a person.
Saying "No" doesn't really help because it's not redirecting the behavior. When something like this happens, making a physical correct, or even shaking a can of coins isn't really the way to go. Try redirecting the game with a toy, or giving the time out if that's not working.
Best of luck! =]