Child with Oppositional Disorder and Sensory Processing Disorder. Help!

I am a P.T. seeing both children and adult patients. I am seeing a 4 year old child diagnosed with sensory and speech impairments and oppositional disorder. He has shown significant improvement in both sensory and speech areas. His teachers are concerned that he can’t understand other students personal space. He seems to often want to grab them or sit near
them (or even sit on them) and the children ask him to move away or not touch and he doesn’t seem to understand it makes them uncomfortable. Does anybody know any articles or any advise I can give the parents or his teachers. Thank you Jackie P.T.