Tim I think it's great that you're doing experiments like this. Do you think you are getting any interesting results or insights?
I have to say that in general I'm skeptical that comparing the kids of siblings is likely to show much-- siblings can just be too different...
And on top of that, in your experiment you have 8 kids on one side of the comparison and 3 on the other. That's most likely just not enough kids to gain any insights IMO.
The most likely thing I think you'd learn about is which traits are dominant and recessive.
However, it sure is fun to explore, isn't it? We've all been surprised by things, so you never know when some neat insight will pop up. If you're enjoying the process than all it takes is an interesting insight every now and then to keep the motivation, and fun, flowing...
