What does it appear that she is doing? Maybe I'm just a raging alcoholic, but this reminds me of bonging beers in high school. That's not, of course, what she is doing, but that's immediately where my mind went, which is why I had to grab a camera.
What she is really doing is, in my opinion, still somewhat wrong. She's letting her sister use this makeshift fire hose to blow into her mouth. Ick.
And now her ear....
They are so weird. They must get this from their dad's side of the family.