Daughter plays with feces

My 6 year old daughter has been diagnosed with AD/HD and ODD.  From the time she was two she would play with her feces and smear it on the walls and furniture.  We had a hard time potty training her because of the defiency from the ODD.  For about a year now we have not had any problems with the smearing and playing with feces, but for the past 8 weeks she has started pooping in her panties again and playing with it.  Sometimes she will dig it out herself.  I dont know what to do.  Her grandparents moved in with us about almost a year ago and a lot of tension was in the family because of the bad relationship her father has with his mom. They moved out a few weeks ago.  Her behavior has gotten better since they left but the feces smearing is still a problem.  Please Help!