What Causes Abnormal Behaviour In A Child?

I have an 8 year old grandson whose behavior seems rather odd at times. He is a bright child, does well in school and has a twin sister. His behavior in school is not a problem but not so at home. He cries a lot and says that no one likes him at school. If you correct him, he says you do not love him and becomes disruptive. He also rearranges furniture in his bedroom and family room on a regular basis, even taking pictures off the wall? We tell him not to do this but he continues almost as if it calms him down. I fear he suffers from anxiety and at times depression. could this be true in a young child of 8?