What does it mean when a dog cobs another dog?

I live on a beach with many dogs. They are all fed, vaccinated, given vet care when needed etc, but they are all free to go where they please. They typically dont, they have a good life here. They are very much pack-oriented.

The smaller puppy (f, around 2 yrs old) is a new addition. I personally have been caring for her as she just finished her treatment for ehrlichia. The larger dog (f, unknown age) is definitely the pack leader. But she will charge the puppy, and other females in the group, and aggressively cob them. It seems endearing, but the puppy definitely still cowers as this behavior USED to be a bit more aggressive in that the larger dog would tumble her..like she couldn't get landing gear down fast enough. Now its just what is depicted in the video.

She cobs me as well when I have clothing covering my legs and torso. I know she respects me and loves me. They are all my babies. Any thoughts?