Get a trainer.
Use a toy to redirect her. All you are doing is ramping her up. Teach her what is appropriate to play with and what isn't. She will learn that toys are to play with and the game stops when she chews on your son.
When it all gets to much, calmly pick her up and put her in a crate with a chew toy or a kong.
It's MICHELLE, scarfish! My name is MICHELLE! Jax is my DOG!
~The strength of one's opinion should not exceed their knowledge on the matter~