My 6 year old daughter scored 149 FSIQ on the WISC-IV by a private tester. My 9 year old daughter was tested by the school psychologist (for IEP qualification purposes for dyslexia) on the WISC-IV and scored dead average.

I thought I had read somewhere that siblings (same parents) are usually within a certain range of each other. Just wondering if anybody else has children with such a drastic difference in scores.