+100000000%The older dog will generally put up with alot of crap before they strike out to say "enough". Its the job of the younger dog to push the limits. As with horses, I tend to allow them to sort it our themselves. If the puppy gets out of line, you can't make an impression they will understand..they are animals not kids..its up to the older dog to draw the line and she will. As far as listening to you, the puppy should be in training to sit, stay and come at your command. There is a chance that if the pup is disrespectful to the older dog , the pup might start that with you and now thats your job to draw THAT line. the pup might not be listening to the older dog..after all its a pup and just trying to play but when it comes to listening to you...thats a must even at 9 weeks.