I have a 7 year old who has always been stubborn and has had periods where he was challenging in his behavior, but who also can be a very sweet, caring boy.  Lately, his behavior has escalated at home and we are concerned.  He is defiant, screams when he gets upset, will refuse to do certain things we ask of him, and has real difficulty managing his frustrations and emotions.  When he is not in the midst of his frustration, he can be insightful, says "I just cannot control myself" when we ask him how he is feeling during his outburst.  His behavior in school is good, he is described as a hard worker and quiet and calm.  My husband and I have made some changes in how we deal with his behavior, focusing on positive reinforcement and trying our best to stay calm and controlled when he has an outburst, but he seems to be able to go for a few days or a few weeks doing just great, but then will have a few days where things are really bad (screaming, yelling, defiant, talking very disrespectfully to us, pushing his sister, antagonistic towards friends).  Recently, he acted this way at his grandparent's house and this was a first.  We are to the point where we are going to talk to our doctor about family counseling and strategies to deal with this, but we are very concerned as it seems to be escalating.  Any advice or insight into what might be going on?