finicky eaters due to childhood abuse ...your ideas please

Hello all,
You were so great with your advice and information in my last discussion...so here goes a really hard one:

I would like to help a grandmother with her little 7.5 year old grandson who she has custody of (along with his 2 younger siblings). The kids were so abused and neglected by the birth parents that you have to have a strong stomache to hear even the bare-bones of the situation. Grandmother is an inspiration to everyone…she has managed to get these kids to become calm, feel safer and fit into school…all without drugs. However, the grandson has an issue around eating foods of certain textures and colors, due to the fact that the children were made to eat feces, etc. This is causing a real problem because he limits what he will eat to the point where he is not eating healthily or enough and the younger siblings tend to follow his example now.

The grandson will not interact with any adults…he is ok but guarded even with children his own age. Grandmother is his world. Therefore having any other adult working with him is impossible, at least right now. However, I felt that perhaps I could teach his grandmother how to turn this around with him. His anger and emotional pain is etched on his face in the form of a permanent scowl and he has difficulty looking someone in the eye, however Grandmother can get him to play and relax with her.

Would anyone have had experience with this sort of thing…perhaps certain words she could use, perhaps EMI (introduced as a game for him)…etc. etc.??? She said she tried everything to coax him, etc., but she had not heard of hypnotherapy until my presentation to her group a couple of weeks ago.

Any ideas at all would be most welcome….

Thank you in advance for all your help,
Grace 