My Jess is 13 months old, and recently we've had a guest puppy in the household, an 11 week old working cocker pup. They play all the time! There are lots of fierce faces and wild eyed snarling and growling, with rough and tumble all around the garden and the house - the little one is constantly trying to hang on to Jess's lip or ear or tail, and she tells him off if he hurts her. She never hurts him. They roll around together, they chase each other, and then they lie down together and get their breath back before they start all over again.
It is just how puppies play. The little one is learning bite inhibition much faster than Jess did, because Jess is teaching him. And they are both so happy.
You mention biting - has any of it drawn blood? And is the little one coming back for more, or is she hiding and trying to get away? If both of them are happy and there are waggy tails, then you've got nothing to worry about. When Poppy meets other dogs, she will have learned from Bella what is appropriate behaviour, and will be polite. (Hopefully!
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