When they say someone has their jaws dropped to the floor out of shock or surprise, then you can likely say that the same thing literally just happened to Senior Sage because she has her jaw dropped to the floor right now as well, she was reeling from astounding shock, seeing Nicki standing before her in the pack house.
The most surprising part was the fact that she wasn't alone, she came with her sister, Tori. Just one word was able to escape from Senior Sage's lips at the moment in a very low manner, setting eyes on them standing and holding hands together. "Wow"
The sisterly bond they have with each other is just something beyond explanation.
Senior Sage stood still where she was, a few feet away from where Nicki and her sister were standing too. She could have approached them and said something first before they did anything, however, she kept standing like a sculpture, still feeling way too stunned to speak or do anything.