My sister was knocked over as a child (5/6 years old). her reasoning ability and behaviour at times are like a kid.Can anything be done to assist her?
You say she was knocked over as a 5/6 yo but how old is she now ? Why would that event have anything to do with her present behavior ? Without a clearer picture of who this person is & the origin of their issues it is impossible to speculate on potential treatment.
A local evaluation would better serve the issues at hand.