Yes, we have 2 gifted dds over here, HG is how I classify them. One might be stronger in language, the other one is stronger in math.
Over the years (they are still young, 4 and 7) they have shown different strengths. When younger one was 1 and talking really well, we thought she was more gifted than her sister. Then her sister had a huge cognitive spurt at 4, and she appeared very gifted.
It is indeed common for siblings to be close to each other. The GDC is the one that cites the 10 point difference. However, if you are talking about MG kids, it is very likely then (the way I see it) for one to be gifted and not the other.
Also, be aware that younger ones are less likely to be formally identified as gifted. Maybe it is because they might be less academic than the older one, or they might find a different niche to shine..
