Whenever Mazzy doesn't want to take pictures, I have a little trick. No, I don't say "cheese". That stopped working years ago.
I ask her to do a "superhero pose".
Like magic, Mazzy drops the whole "Noooo pictures, Moooooooommmm..." and starts mugging for the camera while flailing her arms and bending her knees and doing all sorts of weird gestures that I'm sure no superhero ever made in the history of superheroes.
In fact, I think Mazzy's main frame of reference for "superhero poses" is her friend Charlie who seems to be permanently impersonating Spiderman or Buzz Lightyear or whoever is the superhero du jour.