Back hair -which is behind the body- to "switch" as the head turns... any solutions?

Hi all.. so im really new to this and at a point where i was able to figure out Face tracking. 

So, my model have this Back Hair, which is suppose to go BEHIND the body. so i have it in seperate group AFTER the body.

+puppet

     >Head

     >Body

     >Hair Back

so the head turning is working fine (little choppy but that may be a different topic) but... of course the back hair is NOT inside the "Head" group so whenever the face tracking changes the head direction, it will do nothing to the back hair. 

i understand that the easy solution is put them in the "Head" group in their proper categories (frontal, left profile, right profile, etc)... but that will make the back hair in FRONT of the body, visually, covering the face and the body. 

Then If i have the "Body" group on TOP of the "Head" group, i have some font hair that comes over the body so now, some of those front hair will be covered up by the body... 

So is there any solution to make my "Back Hair" to switch angles as the face turns?

Thank you!