If you go back through the threads, you'll find a few stories...I've recounted mine before (my kids haven't been tested):
I'm one of a sibling group, all ID'd as GT, where one is PG, and the remainder are HG+. The HG+ sibs test within 10 points of each other. The PG sib has about 3 to 4 standard deviations on us (more or less, using the old SBLM, which isn't deviation IQs, so I'm estimating a bit here). All of the HG+ sibs presented differently as young children, with reading, for example, ranging from self-taught before age 3 up to parent taught at nearly age 5. One of us (that would be me) almost wasn't tested because of being perceived as being NT.
I'm sure you've heard it before...if you've seen one GT kid...
