Leah tends to forget that she's smaller than the dogs. She just thinks that they're fuzzy playmates and she has no fear of them.
I think she was trying to do a tonsillectomy on Luna. The amazing thing was how gentle the dog was with her. Luna didn't bark, growl, or bite, she just played along.
Jeremiah has three dogs; Luna, Black Girl, and the newest that yet to be named. They all simply shown up at his door and stayed. He won't turn them away; they seem to understand and appreciate their adoption.